diff --git a/msrest/async_client.py b/msrest/async_client.py
index f749fbe..44f0c42 100644
--- a/msrest/async_client.py
+++ b/msrest/async_client.py
@@ -82,8 +82,8 @@ class AsyncServiceClientMixin:
                         session.request,
                         request.method,
                         request.url,
-                        request.data,
-                        request.headers,
+                        data=request.data,
+                        headers=request.headers,
                         **kwargs
                     )
                 )
@@ -104,8 +104,8 @@ class AsyncServiceClientMixin:
                         session.request,
                         request.method,
                         request.url,
-                        request.data,
-                        request.headers,
+                        data=request.data,
+                        headers=request.headers,
                         **kwargs
                     )
                 )
diff --git a/tests/async/test_async_client.py b/tests/async/test_async_client.py
index c77cd63..16d009f 100644
--- a/tests/async/test_async_client.py
+++ b/tests/async/test_async_client.py
@@ -65,12 +65,12 @@ class TestServiceClient(object):
         await ServiceClient.async_send(mock_client, request)
         session.request.call_count = 0
         mock_client._configure_session.assert_called_with(session)
-        session.request.assert_called_with('GET', None, [], {}, stream=True)
+        session.request.assert_called_with('GET', None, data=[], headers={}, stream=True)
         session.close.assert_called_with()
 
         await ServiceClient.async_send(mock_client, request, headers={'id':'1234'}, content={'Test':'Data'})
         mock_client._configure_session.assert_called_with(session)
-        session.request.assert_called_with('GET', None, '{"Test": "Data"}', {'Content-Length': '16', 'id':'1234'}, stream=True)
+        session.request.assert_called_with('GET', None, data='{"Test": "Data"}', headers={'Content-Length': '16', 'id':'1234'}, stream=True)
         assert session.request.call_count == 1
         session.request.call_count = 0
         session.close.assert_called_with()
@@ -79,7 +79,7 @@ class TestServiceClient(object):
         with pytest.raises(ClientRequestError):
             await ServiceClient.async_send(mock_client, request, headers={'id':'1234'}, content={'Test':'Data'}, test='value')
         mock_client._configure_session.assert_called_with(session, test='value')
-        session.request.assert_called_with('GET', None, '{"Test": "Data"}', {'Content-Length': '16', 'id':'1234'}, stream=True)
+        session.request.assert_called_with('GET', None, data='{"Test": "Data"}', headers={'Content-Length': '16', 'id':'1234'}, stream=True)
         assert session.request.call_count == 1
         session.request.call_count = 0
         session.close.assert_called_with()