diff --git a/tests/test_util.py b/tests/test_util.py
index d535a505..b470053c 100644
--- a/tests/test_util.py
+++ b/tests/test_util.py
@@ -141,5 +141,5 @@ def test_process_group_instantiates_and_start_processes(mock_process):
                                   for i in range(concurrency)], any_order=True)
 
     for process in pg.processes:
-        process.start.assert_called()
+        process.start.assert_called_with()