diff --git a/delete-closed-pr-docs/action.yaml b/delete-closed-pr-docs/action.yaml
index 72c6ab8e..8c8f29e6 100644
--- a/delete-closed-pr-docs/action.yaml
+++ b/delete-closed-pr-docs/action.yaml
@@ -29,7 +29,7 @@ runs:
       id: get-docs-versions
       run: |
         echo "site_name: dummy" > mkdocs.yaml
-        echo ::set-output name=docs-versions::$(mike list | grep "pr-")
+        echo ::set-output name=docs-versions::$(mike list | grep -oP "pr-\w+")
       shell: bash
 
     - name: Find closed docs versions