diff --git a/Cargo.toml b/Cargo.toml
index ca13deceb3df..63bfb7fce413 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -86,7 +86,6 @@ arrow-ipc = { version = "53.1.0", default-features = false, features = [
 arrow-ord = { version = "53.1.0", default-features = false }
 arrow-schema = { version = "53.1.0", default-features = false }
 arrow-string = { version = "53.1.0", default-features = false }
-assertor = "0.0.3"
 async-trait = "0.1.73"
 bigdecimal = "=0.4.1"
 bytes = "1.4"
diff --git a/datafusion/physical-plan/Cargo.toml b/datafusion/physical-plan/Cargo.toml
index a30c93fbc08c..7fcd719539ec 100644
--- a/datafusion/physical-plan/Cargo.toml
+++ b/datafusion/physical-plan/Cargo.toml
@@ -68,7 +68,6 @@ rand = { workspace = true }
 tokio = { workspace = true }
 
 [dev-dependencies]
-assertor = { workspace = true }
 datafusion-functions-aggregate = { workspace = true }
 rstest = { workspace = true }
 rstest_reuse = "0.7.0"
diff --git a/datafusion/physical-plan/src/execution_plan.rs b/datafusion/physical-plan/src/execution_plan.rs
index 7a6430d1b280..e6484452d43e 100644
--- a/datafusion/physical-plan/src/execution_plan.rs
+++ b/datafusion/physical-plan/src/execution_plan.rs
@@ -929,8 +929,6 @@ mod tests {
     use super::*;
     use arrow_array::{DictionaryArray, Int32Array, NullArray, RunArray};
     use arrow_schema::{DataType, Field, Schema, SchemaRef};
-    use assertor::assert_that;
-    use assertor::StringAssertion;
     use std::any::Any;
     use std::sync::Arc;
 
@@ -1100,7 +1098,8 @@ mod tests {
             &vec![0],
         );
         assert!(result.is_err());
-        assert_that!(result.err().unwrap().message().as_ref()).starts_with(
+        assert_starts_with(
+            result.err().unwrap().message().as_ref(),
             "Invalid batch column at '0' has null but schema specifies non-nullable",
         );
         Ok(())
@@ -1124,7 +1123,8 @@ mod tests {
             &vec![0],
         );
         assert!(result.is_err());
-        assert_that!(result.err().unwrap().message().as_ref()).starts_with(
+        assert_starts_with(
+            result.err().unwrap().message().as_ref(),
             "Invalid batch column at '0' has null but schema specifies non-nullable",
         );
         Ok(())
@@ -1147,7 +1147,8 @@ mod tests {
             &vec![0],
         );
         assert!(result.is_err());
-        assert_that!(result.err().unwrap().message().as_ref()).starts_with(
+        assert_starts_with(
+            result.err().unwrap().message().as_ref(),
             "Invalid batch column at '0' has null but schema specifies non-nullable",
         );
         Ok(())
@@ -1189,9 +1190,21 @@ mod tests {
             &vec![0],
         );
         assert!(result.is_err());
-        assert_that!(result.err().unwrap().message().as_ref()).starts_with(
+        assert_starts_with(
+            result.err().unwrap().message().as_ref(),
             "Invalid batch column at '0' has null but schema specifies non-nullable",
         );
         Ok(())
     }
+
+    fn assert_starts_with(actual: impl AsRef<str>, expected_prefix: impl AsRef<str>) {
+        let actual = actual.as_ref();
+        let expected_prefix = expected_prefix.as_ref();
+        assert!(
+            actual.starts_with(expected_prefix),
+            "Expected '{}' to start with '{}'",
+            actual,
+            expected_prefix
+        );
+    }
 }