diff --git a/src/Connection/ElasticConnection.php b/src/Connection/ElasticConnection.php
index dba0f44..314ed2d 100755
--- a/src/Connection/ElasticConnection.php
+++ b/src/Connection/ElasticConnection.php
@@ -429,7 +429,7 @@ private function unsetEmpties(array $haystack) {
                 $haystack[$key] = $this->$selfFn($haystack[$key]);
             }
 
-            if (empty($haystack[$key])) {
+            if (is_array($haystack[$key]) && empty($haystack[$key])) {
                 unset($haystack[$key]);
             }
         }