diff --git a/tests/test_api.py b/tests/test_api.py
index 15177ef..20ad188 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -2,7 +2,7 @@
 from unittest.mock import AsyncMock, MagicMock, patch, sentinel
 
 import pytest
-import serial_asyncio
+import serial_asyncio_fast
 import zigpy.config as config
 
 from zigpy_zigate import api as zigate_api
@@ -32,7 +32,7 @@ async def mock_conn(loop, protocol_factory, **kwargs):
         loop.call_soon(protocol.connection_made, None)
         return None, protocol
 
-    monkeypatch.setattr(serial_asyncio, "create_serial_connection", mock_conn)
+    monkeypatch.setattr(serial_asyncio_fast, "create_serial_connection", mock_conn)
 
     await api.connect()
 
diff --git a/tests/test_uart.py b/tests/test_uart.py
index 0fe026b..bd39def 100644
--- a/tests/test_uart.py
+++ b/tests/test_uart.py
@@ -3,7 +3,7 @@
 import gpiozero
 import pytest
 import serial.tools.list_ports
-import serial_asyncio
+import serial_asyncio_fast
 import zigpy.config
 
 from zigpy_zigate import common, uart
@@ -32,7 +32,7 @@ async def mock_conn(loop, protocol_factory, url, **kwargs):
         assert url.startswith("/") is True
         return None, protocol
 
-    monkeypatch.setattr(serial_asyncio, "create_serial_connection", mock_conn)
+    monkeypatch.setattr(serial_asyncio_fast, "create_serial_connection", mock_conn)
     monkeypatch.setattr(common, "set_pizigate_running_mode", AsyncMock())
     DEVICE_CONFIG = zigpy.config.SCHEMA_DEVICE({zigpy.config.CONF_DEVICE_PATH: port})