diff --git a/src/pytest_mock/_util.py b/src/pytest_mock/_util.py
index ad830ca..d3a732a 100644
--- a/src/pytest_mock/_util.py
+++ b/src/pytest_mock/_util.py
@@ -15,7 +15,7 @@ def get_mock_module(config):
             config.getini("mock_use_standalone_module")
         )
         if use_standalone_module:
-            from unittest import mock
+            import mock
 
             _mock_module = mock
         else:
diff --git a/tox.ini b/tox.ini
index 92bcba7..20273f7 100644
--- a/tox.ini
+++ b/tox.ini
@@ -5,6 +5,8 @@ envlist = py{39,310,311,312,313,314}, norewrite, pytest6
 [testenv]
 deps =
     coverage
+    # Used for standalone mock support.
+    mock
     pytest-asyncio
     pytest6: pytest==6.2.5
 commands =