diff --git a/panel/tests/test_param.py b/panel/tests/test_param.py
index 20ded6e45e..14edefbc8b 100644
--- a/panel/tests/test_param.py
+++ b/panel/tests/test_param.py
@@ -660,9 +660,9 @@ class Test(param.Parameterized):
     assert number.value != 3
     assert test.a == 3
 
-    test.a = 4
-    assert number.value != 4
-    assert test.a == 4
+    pane._widgets['a']._process_events({'value': 4})
+    assert test.a == 3
+    assert number.value == 4
 
 
 def test_set_show_name(document, comm):