diff --git a/core/modules/field/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceFormatterBase.php b/core/modules/field/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceFormatterBase.php
index 2ecaaad..f53a162 100644
--- a/core/modules/field/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceFormatterBase.php
+++ b/core/modules/field/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/formatter/EntityReferenceFormatterBase.php
@@ -58,13 +58,17 @@ public function prepareView(array $entities, $langcode, array &$items) {
       }
     }
 
-    // Iterate through the fieldable entities again to attach the loaded data.
+    // Iterate through the fieldable entities again to attach the loaded
+    // data.
     foreach ($entities as $id => $entity) {
-
+      $rekey = FALSE;
       foreach ($items[$id] as $delta => $item) {
         // If we have a revision-ID, the key uses it as-well.
         $identifier = !empty($item['revision_id']) ? $item['target_id'] . ':' . $item['revision_id'] : $item['target_id'];
         if (!isset($target_entities[$identifier])) {
+          // The entity no longer exists, so remove the key.
+          $rekey = TRUE;
+          unset($items[$id][$delta]);
           continue;
         }
 
@@ -81,6 +85,11 @@ public function prepareView(array $entities, $langcode, array &$items) {
         // Mark item as accessible.
         $items[$id][$delta]['access'] = TRUE;
       }
+
+      if ($rekey) {
+        // Rekey the items array.
+        $items[$id] = array_values($items[$id]);
+      }
     }
   }