diff --git a/lib/datasource/rubygems/get-rubygems-org.ts b/lib/datasource/rubygems/get-rubygems-org.ts
index 489a47f89bddf380f1b9975eb6378f9b3dc5e32e..1ac4f4088d9424ead43338573168ed26b0c7e2a8 100644
--- a/lib/datasource/rubygems/get-rubygems-org.ts
+++ b/lib/datasource/rubygems/get-rubygems-org.ts
@@ -86,13 +86,15 @@ function isDataStale(): boolean {
   return minutesElapsed >= 5;
 }
 
+let _updateRubyGemsVersions: Promise<void> | undefined;
+
 async function syncVersions(): Promise<void> {
   if (isDataStale()) {
-    global.updateRubyGemsVersions =
+    _updateRubyGemsVersions =
       // eslint-disable-next-line @typescript-eslint/no-misused-promises
-      global.updateRubyGemsVersions || updateRubyGemsVersions();
-    await global.updateRubyGemsVersions;
-    delete global.updateRubyGemsVersions;
+      _updateRubyGemsVersions || updateRubyGemsVersions();
+    await _updateRubyGemsVersions;
+    _updateRubyGemsVersions = null;
   }
 }
 
diff --git a/lib/globals.d.ts b/lib/globals.d.ts
index 4bc09bb772d361cc76b3dcef4fc13812d882a19b..ee1198a8760e171e51e3a8e65ce5e0cbe0be1184 100644
--- a/lib/globals.d.ts
+++ b/lib/globals.d.ts
@@ -34,8 +34,6 @@ declare namespace NodeJS {
     renovateCache: Renovate.Cache;
 
     trustLevel?: string;
-
-    updateRubyGemsVersions?: Promise<void>;
   }
 }