diff --git a/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml b/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml
index fdb6746bbeed8..5b39f74de1b9d 100644
--- a/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml
+++ b/x-pack/plugin/src/yamlRestTest/resources/rest-api-spec/test/esql/190_lookup_join.yml
@@ -12,8 +12,6 @@ setup:
       indices.create:
         index: test
         body:
-          settings:
-            number_of_shards: 5
           mappings:
             properties:
               key:
@@ -27,6 +25,7 @@ setup:
           settings:
             index:
               mode: lookup
+            number_of_shards: 1
           mappings:
             properties:
               key: