diff --git a/scripts/ci/gitlab/pipeline/test.yml b/scripts/ci/gitlab/pipeline/test.yml
index b405cfa1eb3a4..8baebb39be6dc 100644
--- a/scripts/ci/gitlab/pipeline/test.yml
+++ b/scripts/ci/gitlab/pipeline/test.yml
@@ -68,10 +68,12 @@ cargo-check-benches:
     - !reference [.rusty-cachier, before_script]
     - !reference [.pipeline-stopper-vars, script]
     # merges in the master branch on PRs
+    - |
+      export BASE=$(curl -s -H "Authorization: Bearer ${GITHUB_PR_TOKEN}" https://api.github.com/repos/paritytech/substrate/pulls/${$CI_COMMIT_REF_NAME} | jq .base.ref)
     - if [ $CI_COMMIT_REF_NAME != "master" ]; then
-        git fetch origin +master:master;
+        git fetch origin +${BASE}:${BASE};
         git fetch origin +$CI_COMMIT_REF_NAME:$CI_COMMIT_REF_NAME;
-        git checkout master;
+        git checkout ${BASE};
         git config user.email "ci@gitlab.parity.io";
         git merge $CI_COMMIT_REF_NAME --verbose --no-edit;
       fi