diff --git a/rules-tests/Php71/Rector/FuncCall/RemoveExtraParametersRector/Fixture/skip_defer_function.php.inc b/rules-tests/Php71/Rector/FuncCall/RemoveExtraParametersRector/Fixture/skip_defer_function.php.inc
new file mode 100644
index 00000000000..885174dbb8b
--- /dev/null
+++ b/rules-tests/Php71/Rector/FuncCall/RemoveExtraParametersRector/Fixture/skip_defer_function.php.inc
@@ -0,0 +1,11 @@
+<?php
+
+// no namespace on purpose to demonstrate the issue
+function defer(string $foo, callable $callback): void
+{
+    $callback($foo);
+}
+
+defer("foo", static function ($bar) {
+    echo $bar;
+});
diff --git a/rules/Php71/Rector/FuncCall/RemoveExtraParametersRector.php b/rules/Php71/Rector/FuncCall/RemoveExtraParametersRector.php
index 83c26beffb9..06f8227ab81 100644
--- a/rules/Php71/Rector/FuncCall/RemoveExtraParametersRector.php
+++ b/rules/Php71/Rector/FuncCall/RemoveExtraParametersRector.php
@@ -87,6 +87,10 @@ public function refactor(Node $node): ?Node
             return null;
         }
 
+        if ($this->shouldSkipFunctionReflection($functionLikeReflection)) {
+            return null;
+        }
+
         $numberOfArguments = count($node->getRawArgs());
         if ($numberOfArguments <= $maximumAllowedParameterCount) {
             return null;
@@ -99,6 +103,18 @@ public function refactor(Node $node): ?Node
         return $node;
     }
 
+    private function shouldSkipFunctionReflection(MethodReflection|FunctionReflection $reflection): bool
+    {
+        if ($reflection instanceof FunctionReflection) {
+            $fileName = (string) $reflection->getFileName();
+            if (str_contains($fileName, 'phpstan.phar')) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     private function shouldSkip(FuncCall | MethodCall | StaticCall $call): bool
     {
         if ($call->args === []) {