diff --git a/Eloquent/Relations/MorphTo.php b/Eloquent/Relations/MorphTo.php
index <HASH>..<HASH> 100644
--- a/Eloquent/Relations/MorphTo.php
+++ b/Eloquent/Relations/MorphTo.php
@@ -138,9 +138,7 @@ class MorphTo extends BelongsTo
      */
     protected function gatherKeysByType($type)
     {
-        return collect($this->dictionary[$type])->map(function ($models) {
-            return head($models)->{$this->foreignKey};
-        })->values()->unique()->all();
+        return array_keys($this->dictionary[$type]);
     }
 
     /**
Simplify gatherKeysByType method (#<I>)