diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 2718f72964c0ec89d71b3c249023bae43fb6a9dc..64112cba6313dc44caadce008ee59ab1bafec9af 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -130,7 +130,7 @@ unittest_py39:
   needs: [build-testenv]
   script:
     # First verify that system Python actually is 3.9
-    - python -c "import sys; assert sys.version.startswith('3.9')"
+    - python3 -c "import sys; assert sys.version.startswith('3.9')"
     - python3 -c "import caosdb; print('CaosDB Version:', caosdb.__version__)"
     - tox