diff --git a/core/modules/migrate/src/Plugin/migrate/destination/EntityFieldStorageConfig.php b/core/modules/migrate/src/Plugin/migrate/destination/EntityFieldStorageConfig.php
index 0b9714a79b..c85e4b08e0 100644
--- a/core/modules/migrate/src/Plugin/migrate/destination/EntityFieldStorageConfig.php
+++ b/core/modules/migrate/src/Plugin/migrate/destination/EntityFieldStorageConfig.php
@@ -73,7 +73,7 @@ public function rollback(array $destination_identifier) {
       $language = $destination_identifier['langcode'];
       unset($destination_identifier['langcode']);
       $destination_identifier = [
-        implode('.', $destination_identifier),
+        0 => implode('.', $destination_identifier),
         'langcode' => $language,
       ];
     }