diff --git a/rest-api-spec/src/main/resources/rest-api-spec/test/search.aggregation/20_terms.yml b/rest-api-spec/src/main/resources/rest-api-spec/test/search.aggregation/20_terms.yml
index 3683ad108e8c2..de4693d13db3a 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/test/search.aggregation/20_terms.yml
+++ b/rest-api-spec/src/main/resources/rest-api-spec/test/search.aggregation/20_terms.yml
@@ -830,6 +830,10 @@ setup:
           { "str": "cow", "number": 1 }
           { "index": {} }
           { "str": "pig", "number": 1 }
+  - do:
+      indices.forcemerge:
+        index: test_1
+        max_num_segments: 1
 
   - do:
       search: