diff --git a/pytest_stf/plugin.py b/pytest_stf/plugin.py
index b27f526..4c33340 100644
--- a/pytest_stf/plugin.py
+++ b/pytest_stf/plugin.py
@@ -49,6 +49,11 @@ def pytest_addoption(parser):
         "--appium_logs",
         help="Appium server log file path"
     )
+    group.addoption(
+        "--stf_avoid_devices",
+        default=os.environ.get('STF_AVOID_DEVICES', None),
+        help="Comma-separated list of device serials to deprioritize during allocation",
+    )
 
 
 def pytest_configure(config):
@@ -113,9 +118,15 @@ def fixture_allocated_phone(pytestconfig, lockable):
         timeout = pytestconfig.getoption('stf_allocation_timeout')
         requirements = parse_requirements(requirements)
 
+        avoid_devices_raw = pytestconfig.getoption('stf_avoid_devices')
+        avoid_list = None
+        if avoid_devices_raw:
+            avoid_list = [s.strip() for s in avoid_devices_raw.split(',') if s.strip()]
+
         with stf.allocation_context(requirements,
                                     wait_timeout=allocation_timeout,
-                                    timeout_seconds=timeout) as device:
+                                    timeout_seconds=timeout,
+                                    avoid_list=avoid_list) as device:
             yield device
     else:
         with lockable.auto_lock(requirements, allocation_timeout) as device:
diff --git a/setup.py b/setup.py
index 1f6828a..5c76bc0 100644
--- a/setup.py
+++ b/setup.py
@@ -22,7 +22,7 @@
     install_requires=[
         "pytest>=5.0",
         "pytest-metadata",
-        "stf-appium-client~=0.12.0",
+        "stf-appium-client @ git+https://github.com/kimikorento-o/stf-appium-python-client.git@44fec0f88626242c3538f482b7edbf9d5860f2f7",
         "pytest-lockable~=0.11.0"],
     # List additional groups of dependencies here (e.g. development
     # dependencies). Users will be able to install these using the "extras"
diff --git a/test/test_plugin.py b/test/test_plugin.py
index 903079f..fb2bc16 100644
--- a/test/test_plugin.py
+++ b/test/test_plugin.py
@@ -42,7 +42,11 @@ def test_plugin_stf(pytester: Pytester, example_stf):
         result = pytester.runpytest('--stf_host=.', '--stf_token=abc', '--phone_requirements=platform=Android')
 
     connect.assert_called_once_with('abc')
-    allocation_context.assert_called_once_with({'platform': 'Android'}, timeout_seconds=1000)
+    allocation_context.assert_called_once_with(
+        {'platform': 'Android'},
+        wait_timeout=mock.ANY,
+        timeout_seconds=mock.ANY,
+        avoid_list=None)
     adb_start.assert_called_once_with()
     appium_server_start.assert_called_once_with()
     appium_server_stop.assert_called_once_with()
@@ -53,6 +57,33 @@ def test_plugin_stf(pytester: Pytester, example_stf):
     result.assert_outcomes(passed=1)
 
 
+def test_plugin_stf_with_avoid_devices(pytester: Pytester, example_stf):
+    """Make sure --stf_avoid_devices is parsed and passed to allocation_context"""
+    with mock.patch('stf_appium_client.StfClient.StfClient.connect'), \
+         mock.patch('stf_appium_client.StfClient.StfClient.allocation_context') as allocation_context, \
+         mock.patch('stf_appium_client.AdbServer.AdbServer.connect'), \
+         mock.patch('stf_appium_client.AppiumServer.AppiumServer.start'), \
+         mock.patch('stf_appium_client.AppiumServer.AppiumServer.stop'), \
+         mock.patch('stf_appium_client.AppiumServer.AppiumServer.get_api_path'), \
+         mock.patch('stf_appium_client.AppiumClient.AppiumClient.start'), \
+         mock.patch('stf_appium_client.AppiumClient.AppiumClient.stop'):
+
+        allocation_context.return_value.__enter__.return_value = {
+            "platform": "Android",
+            "remote_adb_url": "localhost"}
+        result = pytester.runpytest(
+            '--stf_host=.', '--stf_token=abc',
+            '--phone_requirements=platform=Android',
+            '--stf_avoid_devices=ABC123,DEF456')
+
+    allocation_context.assert_called_once_with(
+        {'platform': 'Android'},
+        wait_timeout=mock.ANY,
+        timeout_seconds=mock.ANY,
+        avoid_list=['ABC123', 'DEF456'])
+    result.assert_outcomes(passed=1)
+
+
 def test_plugin_local(pytester: Pytester, example_local):
     """Make sure the plugin works with a local device"""
     # run all tests with pytest
@@ -61,9 +92,9 @@ def test_plugin_local(pytester: Pytester, example_local):
          mock.patch('stf_appium_client.AppiumClient.AppiumClient.start') as appium_client_start, \
          mock.patch('stf_appium_client.AppiumClient.AppiumClient.stop') as appium_client_stop:
 
-        auto_lock.return_value.__enter__.return_value = {
-            "platform": "Android"
-        }
+        auto_lock.return_value.__enter__.return_value = mock.Mock(
+            resource_info={"platform": "Android"}
+        )
         result = pytester.runpytest('--phone_requirements=platform=Android')
         print(result)