diff --git a/library/Director/Objects/ImportSource.php b/library/Director/Objects/ImportSource.php
index 49c78527..3d395e85 100644
--- a/library/Director/Objects/ImportSource.php
+++ b/library/Director/Objects/ImportSource.php
@@ -100,7 +100,7 @@ class ImportSource extends DbObjectWithSettings
             foreach ($data as $key => &$row) {
                 $this->applyModifiersToRow($row);
                 if (null === $row) {
-                    $rejected[] = $row;
+                    $rejected[] = $key;
                 }
             }
         }