diff --git a/patrole_tempest_plugin/rbac_utils.py b/patrole_tempest_plugin/rbac_utils.py
index a7da2d3..5736645 100644
--- a/patrole_tempest_plugin/rbac_utils.py
+++ b/patrole_tempest_plugin/rbac_utils.py
@@ -20,8 +20,8 @@
 
 from oslo_log import log as logging
 from oslo_utils import excutils
-import testtools
 
+from tempest import clients
 from tempest.common import credentials_factory as credentials
 from tempest import config
 
@@ -47,19 +47,13 @@
 
         :param test_obj: An instance of `tempest.test.BaseTestCase`.
         """
-        # Since we are going to instantiate a client manager with
-        # admin credentials, first check if admin is available.
-        if not credentials.is_admin_available(
-                identity_version=test_obj.get_identity_version()):
-            msg = "Missing Identity Admin API credentials in configuration."
-            raise testtools.TestCase.skipException(msg)
-
         # Intialize the admin roles_client to perform role switching.
-        admin_creds = test_obj.get_client_manager(credential_type='admin')
+        admin_mgr = clients.Manager(
+            credentials.get_configured_admin_credentials())
         if test_obj.get_identity_version() == 'v3':
-            admin_roles_client = admin_creds.roles_v3_client
+            admin_roles_client = admin_mgr.roles_v3_client
         else:
-            admin_roles_client = admin_creds.roles_client
+            admin_roles_client = admin_mgr.roles_client
 
         self.admin_roles_client = admin_roles_client
         self.switch_role(test_obj, toggle_rbac_role=False)
diff --git a/patrole_tempest_plugin/tests/unit/fixtures.py b/patrole_tempest_plugin/tests/unit/fixtures.py
index 6b42949..9d53eb9 100644
--- a/patrole_tempest_plugin/tests/unit/fixtures.py
+++ b/patrole_tempest_plugin/tests/unit/fixtures.py
@@ -19,6 +19,8 @@
 import fixtures
 import mock
 
+from tempest import clients
+from tempest.common import credentials_factory as credentials
 from tempest import config
 
 from patrole_tempest_plugin import rbac_utils
@@ -72,10 +74,13 @@
             'get_identity_version.return_value': 'v3'
         }
         self.mock_test_obj = mock.Mock(**test_obj_kwargs)
-        self.mock_time = mock.patch.object(rbac_utils, 'time').start()
 
-        self.roles_v3_client = (
-            self.mock_test_obj.get_client_manager.return_value.roles_v3_client)
+        # Mock out functionality that can't be used by unit tests.
+        self.mock_time = mock.patch.object(rbac_utils, 'time').start()
+        mock.patch.object(
+            credentials, 'get_configured_admin_credentials').start()
+        mock_admin_mgr = mock.patch.object(clients, 'Manager').start()
+        self.roles_v3_client = mock_admin_mgr.return_value.roles_v3_client
 
         self.set_roles(['admin', 'member'], [])