diff --git a/superset/utils/core.py b/superset/utils/core.py
index 084b51332..9b1590b5c 100644
--- a/superset/utils/core.py
+++ b/superset/utils/core.py
@@ -1025,8 +1025,8 @@ def merge_extra_filters(  # pylint: disable=too-many-branches
         for existing in adhoc_filters:
             if (
                 existing["expressionType"] == "SIMPLE"
-                and existing["comparator"] is not None
-                and existing["subject"] is not None
+                and existing.get("comparator") is not None
+                and existing.get("subject") is not None
             ):
                 existing_filters[get_filter_key(existing)] = existing["comparator"]