diff --git a/grizzly/main.py b/grizzly/main.py
index 7ce1a154..2a7ec703 100644
--- a/grizzly/main.py
+++ b/grizzly/main.py
@@ -140,7 +140,7 @@ def main(args):
                     display_mode=display_mode,
                     launch_attempts=args.launch_attempts,
                     post_launch_delay=args.post_launch_delay,
-                    services=ext_services.services if ext_services else None,
+                    services=ext_services,
                 )
                 complete_with_results = session.status.results.total > 0