diff --git a/src/forge/Merge/NewMerge.js b/src/forge/Merge/NewMerge.js
index abb9c3f3..2f210480 100644
--- a/src/forge/Merge/NewMerge.js
+++ b/src/forge/Merge/NewMerge.js
@@ -133,8 +133,8 @@ class NewMerge extends Component {
     const url = `/projects/${projectsId}/pull_requests/check_can_merge.json`;
     axios
       .post(url, {
-        head: merge,
-        base: pull,
+        head: pull,
+        base: merge,
         is_original: merge_head,
         fork_project_id: merge_head ? project_id : undefined
       })