diff --git a/src/Coduo/PHPMatcher/Matcher/CallbackMatcher.php b/src/Coduo/PHPMatcher/Matcher/CallbackMatcher.php
index 9943d526..5d8f6403 100644
--- a/src/Coduo/PHPMatcher/Matcher/CallbackMatcher.php
+++ b/src/Coduo/PHPMatcher/Matcher/CallbackMatcher.php
@@ -17,6 +17,6 @@ public function match($value, $pattern)
      */
     public function canMatch($pattern)
     {
-        return is_callable($pattern);
+        return is_object($pattern) && is_callable($pattern);
     }
 }
diff --git a/tests/Coduo/PHPMatcher/Matcher/CallbackMatcherTest.php b/tests/Coduo/PHPMatcher/Matcher/CallbackMatcherTest.php
index ae869844..f7ce5837 100644
--- a/tests/Coduo/PHPMatcher/Matcher/CallbackMatcherTest.php
+++ b/tests/Coduo/PHPMatcher/Matcher/CallbackMatcherTest.php
@@ -15,6 +15,7 @@ function test_negative_can_match()
     {
         $matcher = new CallbackMatcher();
         $this->assertFalse($matcher->canMatch(new \DateTime()));
+        $this->assertFalse($matcher->canMatch('SIN'));
     }
 
     function test_positive_matches()