diff --git a/server/src/main/java/org/elasticsearch/search/retriever/CompoundRetrieverBuilder.java b/server/src/main/java/org/elasticsearch/search/retriever/CompoundRetrieverBuilder.java
index 8fd00977d418f..f20dc814492bc 100644
--- a/server/src/main/java/org/elasticsearch/search/retriever/CompoundRetrieverBuilder.java
+++ b/server/src/main/java/org/elasticsearch/search/retriever/CompoundRetrieverBuilder.java
@@ -252,6 +252,7 @@ protected SearchSourceBuilder createSearchSourceBuilder(PointInTimeBuilder pit,
         }
         sortBuilders.add(new FieldSortBuilder(FieldSortBuilder.SHARD_DOC_FIELD_NAME));
         sourceBuilder.sort(sortBuilders);
+        return sourceBuilder;
     }
 
     private RankDoc[] getRankDocs(SearchResponse searchResponse) {