diff --git a/feeds_ex_xml_mapping.module b/feeds_ex_xml_mapping.module
index 60653e87e322101082fdd72f5bac0de37592d44a..24855a2712622011fc60d44323a043c482b1dcb4 100644
--- a/feeds_ex_xml_mapping.module
+++ b/feeds_ex_xml_mapping.module
@@ -59,7 +59,10 @@ function feeds_ex_xml_mapping_form_feeds_mapping_form_alter(array &$form, FormSt
     ],
   ];
   // Custom submit handler.
-  $form['#submit'][] = 'feeds_ex_xml_mapping_form_feeds_mapping_form_submit';
+  array_unshift(
+    $form['#submit'],
+    'feeds_ex_xml_mapping_form_feeds_mapping_form_submit'
+  );
 }
 
 /**