diff --git a/lib/Doctrine/ORM/EntityManagerInterface.php b/lib/Doctrine/ORM/EntityManagerInterface.php
index 90f466e8d66..2a4a2a4fbc3 100644
--- a/lib/Doctrine/ORM/EntityManagerInterface.php
+++ b/lib/Doctrine/ORM/EntityManagerInterface.php
@@ -98,9 +98,11 @@ public function transactional($func);
      * If an exception occurs during execution of the function or flushing or transaction commit,
      * the transaction is rolled back, the EntityManager closed and the exception re-thrown.
      *
-     * @param callable $func The function to execute transactionally.
+     * @param callable(): T $func The function to execute transactionally.
+     *
+     * @return T The value returned from the closure.
      *
-     * @return mixed The value returned from the closure.
+     * @template T
      */
     // public function wrapInTransaction(callable $func);