diff --git a/diff-sha.sh b/diff-sha.sh
index 50ae2c3c..ddd08302 100644
--- a/diff-sha.sh
+++ b/diff-sha.sh
@@ -194,7 +194,7 @@ else
       git fetch $EXTRA_ARGS -u --progress origin pull/"$GITHUB_EVENT_PULL_REQUEST_NUMBER"/head:"$CURRENT_BRANCH" 1>/dev/null
     else
       # shellcheck disable=SC2086
-      git fetch $EXTRA_ARGS -u --progress origin "+refs/heads/$TARGET_BRANCH:refs/remotes/origin/$TARGET_BRANCH" "+refs/heads/$CURRENT_BRANCH*:refs/remotes/origin/$CURRENT_BRANCH*" 1>/dev/null
+      git fetch $EXTRA_ARGS -u --progress --deepen="$INPUT_FETCH_DEPTH" origin +refs/heads/"$CURRENT_BRANCH"*:refs/remotes/origin/"$CURRENT_BRANCH"* 1>/dev/null
     fi
     
     if [[ "$INPUT_SINCE_LAST_REMOTE_COMMIT" != "true" ]]; then