diff --git a/rules/PHPUnit100/Rector/Class_/RemoveNamedArgsInDataProviderRector.php b/rules/PHPUnit100/Rector/Class_/RemoveNamedArgsInDataProviderRector.php
index 83914942..d2bc5e1c 100644
--- a/rules/PHPUnit100/Rector/Class_/RemoveNamedArgsInDataProviderRector.php
+++ b/rules/PHPUnit100/Rector/Class_/RemoveNamedArgsInDataProviderRector.php
@@ -128,6 +128,10 @@ private function handleArray(Array_ $array): bool
                 continue;
             }
 
+            if (! $item->key instanceof Expr) {
+                continue;
+            }
+
             if (! $item->key instanceof Int_ && $item->key instanceof Expr) {
                 $item->key = null;
                 $hasChanged = true;