diff --git a/testsuite/MDAnalysisTests/coordinates/test_xdr.py b/testsuite/MDAnalysisTests/coordinates/test_xdr.py
index b8eb68364e..ccd7709d4b 100644
--- a/testsuite/MDAnalysisTests/coordinates/test_xdr.py
+++ b/testsuite/MDAnalysisTests/coordinates/test_xdr.py
@@ -1026,9 +1026,9 @@ def test_persistent_offsets_readonly(self, tmpdir):
 
         shutil.rmtree(tmpdir)
 
-    def test_offset_lock_created(self):
+    def test_offset_lock_created(self, traj):
         assert os.path.exists(
-            XDR.offsets_filename(self.filename, ending="lock")
+            XDR.offsets_filename(traj, ending="lock")
         )