diff --git a/x-pack/plugin/esql/qa/server/mixed-cluster/src/javaRestTest/java/org/elasticsearch/xpack/esql/qa/mixed/MixedClusterEsqlSpecIT.java b/x-pack/plugin/esql/qa/server/mixed-cluster/src/javaRestTest/java/org/elasticsearch/xpack/esql/qa/mixed/MixedClusterEsqlSpecIT.java
index d4b087277df52..9a09401785df0 100644
--- a/x-pack/plugin/esql/qa/server/mixed-cluster/src/javaRestTest/java/org/elasticsearch/xpack/esql/qa/mixed/MixedClusterEsqlSpecIT.java
+++ b/x-pack/plugin/esql/qa/server/mixed-cluster/src/javaRestTest/java/org/elasticsearch/xpack/esql/qa/mixed/MixedClusterEsqlSpecIT.java
@@ -21,7 +21,7 @@
 import java.util.List;
 
 import static org.elasticsearch.xpack.esql.CsvTestUtils.isEnabled;
-import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.JOIN_LOOKUP_V8;
+import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.JOIN_LOOKUP_V9;
 import static org.elasticsearch.xpack.esql.qa.rest.EsqlSpecTestCase.Mode.ASYNC;
 
 public class MixedClusterEsqlSpecIT extends EsqlSpecTestCase {
@@ -96,7 +96,7 @@ protected boolean supportsInferenceTestService() {
 
     @Override
     protected boolean supportsIndexModeLookup() throws IOException {
-        return hasCapabilities(List.of(JOIN_LOOKUP_V8.capabilityName()));
+        return hasCapabilities(List.of(JOIN_LOOKUP_V9.capabilityName()));
     }
 
     @Override
diff --git a/x-pack/plugin/esql/qa/server/multi-clusters/src/javaRestTest/java/org/elasticsearch/xpack/esql/ccq/MultiClusterSpecIT.java b/x-pack/plugin/esql/qa/server/multi-clusters/src/javaRestTest/java/org/elasticsearch/xpack/esql/ccq/MultiClusterSpecIT.java
index d7c57e23b7147..a809216d3beb3 100644
--- a/x-pack/plugin/esql/qa/server/multi-clusters/src/javaRestTest/java/org/elasticsearch/xpack/esql/ccq/MultiClusterSpecIT.java
+++ b/x-pack/plugin/esql/qa/server/multi-clusters/src/javaRestTest/java/org/elasticsearch/xpack/esql/ccq/MultiClusterSpecIT.java
@@ -48,7 +48,7 @@
 import static org.elasticsearch.xpack.esql.EsqlTestUtils.classpathResources;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.INLINESTATS;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.INLINESTATS_V2;
-import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.JOIN_LOOKUP_V8;
+import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.JOIN_LOOKUP_V9;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.JOIN_PLANNING_V1;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.METADATA_FIELDS_REMOTE_TEST;
 import static org.elasticsearch.xpack.esql.qa.rest.EsqlSpecTestCase.Mode.SYNC;
@@ -124,7 +124,7 @@ protected void shouldSkipTest(String testName) throws IOException {
         assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(INLINESTATS.capabilityName()));
         assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(INLINESTATS_V2.capabilityName()));
         assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(JOIN_PLANNING_V1.capabilityName()));
-        assumeFalse("LOOKUP JOIN not yet supported in CCS", testCase.requiredCapabilities.contains(JOIN_LOOKUP_V8.capabilityName()));
+        assumeFalse("LOOKUP JOIN not yet supported in CCS", testCase.requiredCapabilities.contains(JOIN_LOOKUP_V9.capabilityName()));
     }
 
     private TestFeatureService remoteFeaturesService() throws IOException {
@@ -283,8 +283,8 @@ protected boolean supportsInferenceTestService() {
 
     @Override
     protected boolean supportsIndexModeLookup() throws IOException {
-        // CCS does not yet support JOIN_LOOKUP_V8 and clusters falsely report they have this capability
-        // return hasCapabilities(List.of(JOIN_LOOKUP_V8.capabilityName()));
+        // CCS does not yet support JOIN_LOOKUP_V9 and clusters falsely report they have this capability
+        // return hasCapabilities(List.of(JOIN_LOOKUP_V9.capabilityName()));
         return false;
     }
 }
diff --git a/x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RequestIndexFilteringTestCase.java b/x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RequestIndexFilteringTestCase.java
index 355c403ce2a86..a83b6cf2e906c 100644
--- a/x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RequestIndexFilteringTestCase.java
+++ b/x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RequestIndexFilteringTestCase.java
@@ -221,7 +221,7 @@ public void testIndicesDontExist() throws IOException {
         assertThat(e.getMessage(), containsString("index_not_found_exception"));
         assertThat(e.getMessage(), containsString("no such index [foo]"));
 
-        if (EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled()) {
+        if (EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled()) {
             e = expectThrows(
                 ResponseException.class,
                 () -> runEsql(timestampFilter("gte", "2020-01-01").query("FROM test1 | LOOKUP JOIN foo ON id1"))
diff --git a/x-pack/plugin/esql/qa/testFixtures/src/main/resources/lookup-join.csv-spec b/x-pack/plugin/esql/qa/testFixtures/src/main/resources/lookup-join.csv-spec
index 39638899cf6b6..309386228b1c8 100644
--- a/x-pack/plugin/esql/qa/testFixtures/src/main/resources/lookup-join.csv-spec
+++ b/x-pack/plugin/esql/qa/testFixtures/src/main/resources/lookup-join.csv-spec
@@ -8,7 +8,7 @@
 ###############################################
 
 basicOnTheDataNode
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | EVAL language_code = languages
@@ -25,7 +25,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 basicRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW language_code = 1
 | LOOKUP JOIN languages_lookup ON language_code
@@ -36,7 +36,7 @@ language_code:integer  | language_name:keyword
 ;
 
 basicOnTheCoordinator
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -53,7 +53,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 subsequentEvalOnTheDataNode
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | EVAL language_code = languages
@@ -71,7 +71,7 @@ emp_no:integer | language_code:integer | language_name:keyword | language_code_x
 ;
 
 subsequentEvalOnTheCoordinator
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -89,7 +89,7 @@ emp_no:integer | language_code:integer | language_name:keyword | language_code_x
 ;
 
 sortEvalBeforeLookup
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -106,7 +106,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 nonUniqueLeftKeyOnTheDataNode
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | WHERE emp_no <= 10030
@@ -130,7 +130,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 nonUniqueRightKeyOnTheDataNode
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | EVAL language_code = emp_no % 10
@@ -150,7 +150,7 @@ emp_no:integer | language_code:integer | language_name:keyword       | country:k
 ;
 
 nonUniqueRightKeyOnTheCoordinator
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -170,7 +170,7 @@ emp_no:integer | language_code:integer | language_name:keyword       | country:k
 ;
 
 nonUniqueRightKeyFromRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW language_code = 2
 | LOOKUP JOIN languages_lookup_non_unique_key ON language_code
@@ -183,8 +183,7 @@ language_code:integer | language_name:keyword       | country:keyword
 ;
 
 repeatedIndexOnFrom
-required_capability: join_lookup_v8
-required_capability: join_lookup_repeated_index_from
+required_capability: join_lookup_v9
 
 FROM languages_lookup
 | LOOKUP JOIN languages_lookup ON language_code
@@ -202,7 +201,7 @@ dropAllLookedUpFieldsOnTheDataNode-Ignore
 // Depends on
 // https://github.com/elastic/elasticsearch/issues/118778
 // https://github.com/elastic/elasticsearch/issues/118781
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | EVAL language_code = emp_no % 10
@@ -223,7 +222,7 @@ dropAllLookedUpFieldsOnTheCoordinator-Ignore
 // Depends on
 // https://github.com/elastic/elasticsearch/issues/118778
 // https://github.com/elastic/elasticsearch/issues/118781
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -248,7 +247,7 @@ emp_no:integer
 ###############################################
 
 filterOnLeftSide
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | EVAL language_code = languages
@@ -265,7 +264,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 filterOnRightSide
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -281,7 +280,7 @@ FROM sample_data
 ;
 
 filterOnRightSideAfterStats
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -294,7 +293,7 @@ count:long | type:keyword
 ;
 
 filterOnJoinKey
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | EVAL language_code = languages
@@ -309,7 +308,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 filterOnJoinKeyAndRightSide
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | WHERE emp_no < 10006
@@ -326,7 +325,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 filterOnRightSideOnTheCoordinator
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -342,7 +341,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 filterOnJoinKeyOnTheCoordinator
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -358,7 +357,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 filterOnJoinKeyAndRightSideOnTheCoordinator
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | SORT emp_no
@@ -375,7 +374,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 filterOnTheDataNodeThenFilterOnTheCoordinator
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | EVAL language_code = languages
@@ -396,7 +395,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ###########################################################################
 
 nullJoinKeyOnTheDataNode
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | WHERE emp_no < 10004
@@ -413,7 +412,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 mvJoinKeyOnTheDataNode
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | WHERE 10003 < emp_no AND emp_no < 10008
@@ -431,7 +430,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 ;
 
 mvJoinKeyFromRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW language_code = [4, 5, 6, 7]
 | LOOKUP JOIN languages_lookup_non_unique_key ON language_code
@@ -444,7 +443,7 @@ language_code:integer | language_name:keyword       | country:keyword
 ;
 
 mvJoinKeyFromRowExpanded
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW language_code = [4, 5, 6, 7, 8]
 | MV_EXPAND language_code
@@ -466,7 +465,7 @@ language_code:integer | language_name:keyword       | country:keyword
 ###########################################################################
 
 joinOnNestedField
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM employees
 | WHERE 10000 < emp_no AND emp_no < 10006
@@ -486,7 +485,7 @@ emp_no:integer | language.id:integer | language.name:text
 
 
 joinOnNestedFieldRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW language.code = "EN"
 | LOOKUP JOIN languages_nested_fields ON language.code
@@ -499,7 +498,7 @@ language.id:integer | language.code:keyword | language.name.keyword:keyword
 
 
 joinOnNestedNestedFieldRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW language.name.keyword = "English"
 | LOOKUP JOIN languages_nested_fields ON language.name.keyword
@@ -515,7 +514,7 @@ language.id:integer | language.name:text | language.name.keyword:keyword
 ###############################################
 
 lookupIPFromRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", right = "right"
 | LOOKUP JOIN clientips_lookup ON client_ip
@@ -526,7 +525,7 @@ left         | 172.21.0.5        | right         | Development
 ;
 
 lookupIPFromKeepRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", right = "right"
 | KEEP left, client_ip, right
@@ -538,7 +537,7 @@ left         | 172.21.0.5        | right         | Development
 ;
 
 lookupIPFromRowWithShadowing
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", env = "env", right = "right"
 | LOOKUP JOIN clientips_lookup ON client_ip
@@ -549,7 +548,7 @@ left         | 172.21.0.5        | right         | Development
 ;
 
 lookupIPFromRowWithShadowingKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", env = "env", right = "right"
 | EVAL client_ip = client_ip::keyword
@@ -562,7 +561,7 @@ left         | 172.21.0.5        | right         | Development
 ;
 
 lookupIPFromRowWithShadowingKeepReordered
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", env = "env", right = "right"
 | EVAL client_ip = client_ip::keyword
@@ -575,7 +574,7 @@ right         | Development | 172.21.0.5
 ;
 
 lookupIPFromIndex
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -594,7 +593,7 @@ ignoreOrder:true
 ;
 
 lookupIPFromIndexKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -614,7 +613,7 @@ ignoreOrder:true
 ;
 
 lookupIPFromIndexKeepKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | KEEP client_ip, event_duration, @timestamp, message
@@ -636,7 +635,7 @@ timestamp:date           | client_ip:keyword | event_duration:long | msg:keyword
 ;
 
 lookupIPFromIndexStats
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -652,7 +651,7 @@ count:long | env:keyword
 ;
 
 lookupIPFromIndexStatsKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -669,7 +668,7 @@ count:long | env:keyword
 ;
 
 statsAndLookupIPFromIndex
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -690,7 +689,7 @@ count:long | client_ip:keyword | env:keyword
 ###############################################
 
 lookupMessageFromRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", message = "Connected to 10.1.0.1", right = "right"
 | LOOKUP JOIN message_types_lookup ON message
@@ -701,7 +700,7 @@ left         | Connected to 10.1.0.1 | right         | Success
 ;
 
 lookupMessageFromKeepRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", message = "Connected to 10.1.0.1", right = "right"
 | KEEP left, message, right
@@ -713,7 +712,7 @@ left         | Connected to 10.1.0.1 | right         | Success
 ;
 
 lookupMessageFromRowWithShadowing
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", message = "Connected to 10.1.0.1", type = "unknown", right = "right"
 | LOOKUP JOIN message_types_lookup ON message
@@ -724,7 +723,7 @@ left         | Connected to 10.1.0.1 | right         | Success
 ;
 
 lookupMessageFromRowWithShadowingKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", message = "Connected to 10.1.0.1", type = "unknown", right = "right"
 | LOOKUP JOIN message_types_lookup ON message
@@ -736,7 +735,7 @@ left         | Connected to 10.1.0.1 | right         | Success
 ;
 
 lookupMessageFromIndex
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -754,7 +753,7 @@ ignoreOrder:true
 ;
 
 lookupMessageFromIndexKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -773,7 +772,7 @@ ignoreOrder:true
 ;
 
 lookupMessageFromIndexKeepKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | KEEP client_ip, event_duration, @timestamp, message
@@ -793,7 +792,7 @@ ignoreOrder:true
 ;
 
 lookupMessageFromIndexKeepReordered
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -812,7 +811,7 @@ Success      | 172.21.2.162 | 3450233             | Connected to 10.1.0.3
 ;
 
 lookupMessageFromIndexStats
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -827,7 +826,7 @@ count:long | type:keyword
 ;
 
 lookupMessageFromIndexStatsKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -843,7 +842,7 @@ count:long | type:keyword
 ;
 
 statsAndLookupMessageFromIndex
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | STATS count = count(message) BY message
@@ -861,7 +860,7 @@ count:long | type:keyword | message:keyword
 ;
 
 lookupMessageFromIndexTwice
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -883,7 +882,7 @@ ignoreOrder:true
 ;
 
 lookupMessageFromIndexTwiceKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -906,7 +905,7 @@ ignoreOrder:true
 ;
 
 lookupMessageFromIndexTwiceFullyShadowing
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | LOOKUP JOIN message_types_lookup ON message
@@ -930,7 +929,7 @@ ignoreOrder:true
 ###############################################
 
 lookupIPAndMessageFromRow
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", right = "right"
 | LOOKUP JOIN clientips_lookup ON client_ip
@@ -942,7 +941,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowKeepBefore
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", right = "right"
 | KEEP left, client_ip, message, right
@@ -955,7 +954,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowKeepBetween
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", right = "right"
 | LOOKUP JOIN clientips_lookup ON client_ip
@@ -968,7 +967,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowKeepAfter
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", right = "right"
 | LOOKUP JOIN clientips_lookup ON client_ip
@@ -981,7 +980,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowWithShadowing
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", env = "env", type = "type", right = "right"
 | LOOKUP JOIN clientips_lookup ON client_ip
@@ -993,7 +992,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowWithShadowingKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", env = "env", right = "right"
 | EVAL client_ip = client_ip::keyword
@@ -1007,7 +1006,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowWithShadowingKeepKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", env = "env", right = "right"
 | EVAL client_ip = client_ip::keyword
@@ -1022,7 +1021,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowWithShadowingKeepKeepKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", env = "env", right = "right"
 | EVAL client_ip = client_ip::keyword
@@ -1038,7 +1037,7 @@ left         | 172.21.0.5        | Connected to 10.1.0.1 | right         | Devel
 ;
 
 lookupIPAndMessageFromRowWithShadowingKeepReordered
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 ROW left = "left", client_ip = "172.21.0.5", message = "Connected to 10.1.0.1", env = "env", right = "right"
 | EVAL client_ip = client_ip::keyword
@@ -1052,7 +1051,7 @@ right         | Development  | Success      | 172.21.0.5
 ;
 
 lookupIPAndMessageFromIndex
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -1072,7 +1071,7 @@ ignoreOrder:true
 ;
 
 lookupIPAndMessageFromIndexKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -1093,7 +1092,7 @@ ignoreOrder:true
 ;
 
 lookupIPAndMessageFromIndexStats
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -1111,7 +1110,7 @@ count:long | env:keyword | type:keyword
 ;
 
 lookupIPAndMessageFromIndexStatsKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -1130,7 +1129,7 @@ count:long | env:keyword | type:keyword
 ;
 
 statsAndLookupIPAndMessageFromIndex
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -1149,7 +1148,7 @@ count:long | client_ip:keyword | message:keyword       | env:keyword | type:keyw
 ;
 
 lookupIPAndMessageFromIndexChainedEvalKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
@@ -1171,7 +1170,7 @@ ignoreOrder:true
 ;
 
 lookupIPAndMessageFromIndexChainedRenameKeep
-required_capability: join_lookup_v8
+required_capability: join_lookup_v9
 
 FROM sample_data
 | EVAL client_ip = client_ip::keyword
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/action/EsqlCapabilities.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/action/EsqlCapabilities.java
index b1b11ccb09c86..22f7937ccf4ff 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/action/EsqlCapabilities.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/action/EsqlCapabilities.java
@@ -560,12 +560,7 @@ public enum Cap {
         /**
          * LOOKUP JOIN
          */
-        JOIN_LOOKUP_V8(Build.current().isSnapshot()),
-
-        /**
-         * LOOKUP JOIN with the same index as the FROM
-         */
-        JOIN_LOOKUP_REPEATED_INDEX_FROM(JOIN_LOOKUP_V8.isEnabled()),
+        JOIN_LOOKUP_V9(Build.current().isSnapshot()),
 
         /**
          * Fix for https://github.com/elastic/elasticsearch/issues/117054
diff --git a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/planner/LocalExecutionPlanner.java b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/planner/LocalExecutionPlanner.java
index dedc612071434..c40263baa6566 100644
--- a/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/planner/LocalExecutionPlanner.java
+++ b/x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/planner/LocalExecutionPlanner.java
@@ -575,6 +575,15 @@ private PhysicalOperation planLookupJoin(LookupJoinExec join, LocalExecutionPlan
         if (localSourceExec.indexMode() != IndexMode.LOOKUP) {
             throw new IllegalArgumentException("can't plan [" + join + "]");
         }
+        Map<String, IndexMode> indicesWithModes = localSourceExec.index().indexNameWithModes();
+        if (indicesWithModes.size() != 1) {
+            throw new IllegalArgumentException("can't plan [" + join + "], found more than 1 index");
+        }
+        var entry = indicesWithModes.entrySet().iterator().next();
+        if (entry.getValue() != IndexMode.LOOKUP) {
+            throw new IllegalArgumentException("can't plan [" + join + "], found index with mode [" + entry.getValue() + "]");
+        }
+        String indexName = entry.getKey();
         List<Layout.ChannelAndType> matchFields = new ArrayList<>(join.leftFields().size());
         for (Attribute m : join.leftFields()) {
             Layout.ChannelAndType t = source.layout.get(m.id());
@@ -595,7 +604,7 @@ private PhysicalOperation planLookupJoin(LookupJoinExec join, LocalExecutionPlan
                 matchFields.getFirst().channel(),
                 lookupFromIndexService,
                 matchFields.getFirst().type(),
-                localSourceExec.index().name(),
+                indexName,
                 join.leftFields().getFirst().name(),
                 join.addedFields().stream().map(f -> (NamedExpression) f).toList(),
                 join.source()
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/CsvTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/CsvTests.java
index 1e0374c648579..76744957ff5fc 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/CsvTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/CsvTests.java
@@ -263,7 +263,7 @@ public final void test() throws Throwable {
             );
             assumeFalse(
                 "lookup join disabled for csv tests",
-                testCase.requiredCapabilities.contains(EsqlCapabilities.Cap.JOIN_LOOKUP_V8.capabilityName())
+                testCase.requiredCapabilities.contains(EsqlCapabilities.Cap.JOIN_LOOKUP_V9.capabilityName())
             );
             assumeFalse(
                 "can't use TERM function in csv tests",
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/AnalyzerTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/AnalyzerTests.java
index 674eda8916c5a..be15bb7de8b44 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/AnalyzerTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/AnalyzerTests.java
@@ -2140,7 +2140,7 @@ public void testLookupMatchTypeWrong() {
     }
 
     public void testLookupJoinUnknownIndex() {
-        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         String errorMessage = "Unknown index [foobar]";
         IndexResolution missingLookupIndex = IndexResolution.invalid(errorMessage);
@@ -2169,7 +2169,7 @@ public void testLookupJoinUnknownIndex() {
     }
 
     public void testLookupJoinUnknownField() {
-        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         String query = "FROM test | LOOKUP JOIN languages_lookup ON last_name";
         String errorMessage = "1:45: Unknown column [last_name] in right side of join";
@@ -2192,7 +2192,7 @@ public void testLookupJoinUnknownField() {
     }
 
     public void testMultipleLookupJoinsGiveDifferentAttributes() {
-        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         // The field attributes that get contributed by different LOOKUP JOIN commands must have different name ids,
         // even if they have the same names. Otherwise, things like dependency analysis - like in PruneColumns - cannot work based on
@@ -2222,7 +2222,7 @@ public void testMultipleLookupJoinsGiveDifferentAttributes() {
     }
 
     public void testLookupJoinIndexMode() {
-        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         var indexResolution = AnalyzerTestUtils.expandedDefaultIndexResolution();
         var lookupResolution = AnalyzerTestUtils.defaultLookupResolution();
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/ParsingTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/ParsingTests.java
index 549ddce03c206..2f6cf46f2e2b1 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/ParsingTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/ParsingTests.java
@@ -113,7 +113,7 @@ public void testTooBigQuery() {
     }
 
     public void testJoinOnConstant() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertEquals(
             "1:55: JOIN ON clause only supports fields at the moment, found [123]",
             error("row languages = 1, gender = \"f\" | lookup join test on 123")
@@ -129,7 +129,7 @@ public void testJoinOnConstant() {
     }
 
     public void testJoinOnMultipleFields() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertEquals(
             "1:35: JOIN ON clause only supports one field at the moment, found [2]",
             error("row languages = 1, gender = \"f\" | lookup join test on gender, languages")
@@ -137,7 +137,7 @@ public void testJoinOnMultipleFields() {
     }
 
     public void testJoinTwiceOnTheSameField() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertEquals(
             "1:35: JOIN ON clause only supports one field at the moment, found [2]",
             error("row languages = 1, gender = \"f\" | lookup join test on languages, languages")
@@ -145,7 +145,7 @@ public void testJoinTwiceOnTheSameField() {
     }
 
     public void testJoinTwiceOnTheSameField_TwoLookups() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertEquals(
             "1:80: JOIN ON clause only supports one field at the moment, found [2]",
             error("row languages = 1, gender = \"f\" | lookup join test on languages | eval x = 1 | lookup join test on gender, gender")
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/VerifierTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/VerifierTests.java
index 43d764ab2007d..533cc59b824ce 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/VerifierTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/VerifierTests.java
@@ -1974,7 +1974,7 @@ public void testSortByAggregate() {
     }
 
     public void testLookupJoinDataTypeMismatch() {
-        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("requires LOOKUP JOIN capability", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         query("FROM test | EVAL language_code = languages | LOOKUP JOIN languages_lookup ON language_code");
 
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/LogicalPlanOptimizerTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/LogicalPlanOptimizerTests.java
index 7e65cb045b26e..672eef7076c64 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/LogicalPlanOptimizerTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/LogicalPlanOptimizerTests.java
@@ -4927,7 +4927,7 @@ public void testPlanSanityCheck() throws Exception {
     }
 
     public void testPlanSanityCheckWithBinaryPlans() throws Exception {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         var plan = optimizedPlan("""
               FROM test
@@ -6003,7 +6003,7 @@ public void testLookupStats() {
      *     \_EsRelation[languages_lookup][LOOKUP][language_code{f}#18, language_name{f}#19]
      */
     public void testLookupJoinPushDownFilterOnJoinKeyWithRename() {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         String query = """
               FROM test
@@ -6045,7 +6045,7 @@ public void testLookupJoinPushDownFilterOnJoinKeyWithRename() {
      *     \_EsRelation[languages_lookup][LOOKUP][language_code{f}#18, language_name{f}#19]
      */
     public void testLookupJoinPushDownFilterOnLeftSideField() {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         String query = """
               FROM test
@@ -6088,7 +6088,7 @@ public void testLookupJoinPushDownFilterOnLeftSideField() {
      *       \_EsRelation[languages_lookup][LOOKUP][language_code{f}#18, language_name{f}#19]
      */
     public void testLookupJoinPushDownDisabledForLookupField() {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         String query = """
               FROM test
@@ -6132,7 +6132,7 @@ public void testLookupJoinPushDownDisabledForLookupField() {
      *       \_EsRelation[languages_lookup][LOOKUP][language_code{f}#19, language_name{f}#20]
      */
     public void testLookupJoinPushDownSeparatedForConjunctionBetweenLeftAndRightField() {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         String query = """
               FROM test
@@ -6183,7 +6183,7 @@ public void testLookupJoinPushDownSeparatedForConjunctionBetweenLeftAndRightFiel
      *       \_EsRelation[languages_lookup][LOOKUP][language_code{f}#19, language_name{f}#20]
      */
     public void testLookupJoinPushDownDisabledForDisjunctionBetweenLeftAndRightField() {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         String query = """
               FROM test
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/PhysicalPlanOptimizerTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/PhysicalPlanOptimizerTests.java
index ac56d13f870f7..80f2772945e93 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/PhysicalPlanOptimizerTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/optimizer/PhysicalPlanOptimizerTests.java
@@ -2615,7 +2615,7 @@ public void testVerifierOnMissingReferences() {
     }
 
     public void testVerifierOnMissingReferencesWithBinaryPlans() throws Exception {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         // Do not assert serialization:
         // This will have a LookupJoinExec, which is not serializable because it doesn't leave the coordinator.
@@ -7298,7 +7298,7 @@ public void testLookupThenTopN() {
     }
 
     public void testLookupJoinFieldLoading() throws Exception {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         TestDataSource data = dataSetWithLookupIndices(Map.of("lookup_index", List.of("first_name", "foo", "bar", "baz")));
 
@@ -7375,7 +7375,7 @@ public void testLookupJoinFieldLoading() throws Exception {
     }
 
     public void testLookupJoinFieldLoadingTwoLookups() throws Exception {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         TestDataSource data = dataSetWithLookupIndices(
             Map.of(
@@ -7429,7 +7429,7 @@ public void testLookupJoinFieldLoadingTwoLookups() throws Exception {
 
     @AwaitsFix(bugUrl = "https://github.com/elastic/elasticsearch/issues/119082")
     public void testLookupJoinFieldLoadingTwoLookupsProjectInBetween() throws Exception {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         TestDataSource data = dataSetWithLookupIndices(
             Map.of(
@@ -7470,7 +7470,7 @@ public void testLookupJoinFieldLoadingTwoLookupsProjectInBetween() throws Except
 
     @AwaitsFix(bugUrl = "https://github.com/elastic/elasticsearch/issues/118778")
     public void testLookupJoinFieldLoadingDropAllFields() throws Exception {
-        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("Requires LOOKUP JOIN", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
 
         TestDataSource data = dataSetWithLookupIndices(Map.of("lookup_index", List.of("first_name", "foo", "bar", "baz")));
 
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/session/IndexResolverFieldNamesTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/session/IndexResolverFieldNamesTests.java
index 60bdf4e7f73d3..b344bd6b63255 100644
--- a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/session/IndexResolverFieldNamesTests.java
+++ b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/session/IndexResolverFieldNamesTests.java
@@ -1365,7 +1365,7 @@ public void testMetrics() {
     }
 
     public void testLookupJoin() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             "FROM employees | KEEP languages | RENAME languages AS language_code | LOOKUP JOIN languages_lookup ON language_code",
             Set.of("languages", "languages.*", "language_code", "language_code.*"),
@@ -1374,7 +1374,7 @@ public void testLookupJoin() {
     }
 
     public void testLookupJoinKeep() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM employees
@@ -1388,7 +1388,7 @@ public void testLookupJoinKeep() {
     }
 
     public void testLookupJoinKeepWildcard() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM employees
@@ -1402,7 +1402,7 @@ public void testLookupJoinKeepWildcard() {
     }
 
     public void testMultiLookupJoin() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1415,7 +1415,7 @@ public void testMultiLookupJoin() {
     }
 
     public void testMultiLookupJoinKeepBefore() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1429,7 +1429,7 @@ public void testMultiLookupJoinKeepBefore() {
     }
 
     public void testMultiLookupJoinKeepBetween() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1454,7 +1454,7 @@ public void testMultiLookupJoinKeepBetween() {
     }
 
     public void testMultiLookupJoinKeepAfter() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1481,7 +1481,7 @@ public void testMultiLookupJoinKeepAfter() {
     }
 
     public void testMultiLookupJoinKeepAfterWildcard() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1495,7 +1495,7 @@ public void testMultiLookupJoinKeepAfterWildcard() {
     }
 
     public void testMultiLookupJoinSameIndex() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1509,7 +1509,7 @@ public void testMultiLookupJoinSameIndex() {
     }
 
     public void testMultiLookupJoinSameIndexKeepBefore() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1524,7 +1524,7 @@ public void testMultiLookupJoinSameIndexKeepBefore() {
     }
 
     public void testMultiLookupJoinSameIndexKeepBetween() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
@@ -1550,7 +1550,7 @@ public void testMultiLookupJoinSameIndexKeepBetween() {
     }
 
     public void testMultiLookupJoinSameIndexKeepAfter() {
-        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V8.isEnabled());
+        assumeTrue("LOOKUP JOIN available as snapshot only", EsqlCapabilities.Cap.JOIN_LOOKUP_V9.isEnabled());
         assertFieldNames(
             """
                 FROM sample_data
diff --git a/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml b/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml
index 5b39f74de1b9d..57d2dac23026b 100644
--- a/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml
+++ b/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml
@@ -6,7 +6,7 @@ setup:
         - method: POST
           path: /_query
           parameters: []
-          capabilities: [join_lookup_v8]
+          capabilities: [join_lookup_v9]
       reason: "uses LOOKUP JOIN"
   - do:
       indices.create:
@@ -32,6 +32,13 @@ setup:
                 type: long
               color:
                 type: keyword
+  - do:
+      indices.update_aliases:
+        body:
+          actions:
+            - add:
+                index: test-lookup
+                alias: test-lookup-alias
   - do:
       bulk:
         index: "test"
@@ -75,3 +82,45 @@ non-lookup index:
 
   - match: { error.type: "verification_exception" }
   - contains: { error.reason: "Found 1 problem\nline 1:43: invalid [test] resolution in lookup mode to an index in [standard] mode" }
+
+---
+alias:
+  - do:
+      esql.query:
+        body:
+          query: 'FROM test | SORT key | LOOKUP JOIN `test-lookup-alias` ON key | LIMIT 3'
+
+  - match: {columns.0.name: "key"}
+  - match: {columns.0.type: "long"}
+  - match: {columns.1.name: "color"}
+  - match: {columns.1.type: "keyword"}
+  - match: {values.0: [1, "cyan"]}
+  - match: {values.1: [2, "yellow"]}
+
+---
+alias-repeated-alias:
+  - do:
+      esql.query:
+        body:
+          query: 'FROM test-lookup-alias | SORT key | LOOKUP JOIN `test-lookup-alias` ON key | LIMIT 3'
+
+  - match: {columns.0.name: "key"}
+  - match: {columns.0.type: "long"}
+  - match: {columns.1.name: "color"}
+  - match: {columns.1.type: "keyword"}
+  - match: {values.0: [1, "cyan"]}
+  - match: {values.1: [2, "yellow"]}
+
+---
+alias-repeated-index:
+  - do:
+      esql.query:
+        body:
+          query: 'FROM test-lookup | SORT key | LOOKUP JOIN `test-lookup-alias` ON key | LIMIT 3'
+
+  - match: {columns.0.name: "key"}
+  - match: {columns.0.type: "long"}
+  - match: {columns.1.name: "color"}
+  - match: {columns.1.type: "keyword"}
+  - match: {values.0: [1, "cyan"]}
+  - match: {values.1: [2, "yellow"]}