diff --git a/docs/topics/testing.txt b/docs/topics/testing.txt
index d7820cbe46..f4f289ccd7 100644
--- a/docs/topics/testing.txt
+++ b/docs/topics/testing.txt
@@ -479,7 +479,7 @@ arguments at time of construction:
     Once you have a ``Client`` instance, you can call any of the following
     methods:
 
-    .. method:: Client.get(path, data={})
+    .. method:: Client.get(path, data={}, **extra)
 
         Makes a GET request on the provided ``path`` and returns a ``Response``
         object, which is documented below.
@@ -494,7 +494,18 @@ arguments at time of construction:
 
             /customers/details/?name=fred&age=7
 
-    .. method:: Client.post(path, data={}, content_type=MULTIPART_CONTENT)
+        The ``extra`` keyword arguments parameter can be used to specify
+        headers to be sent in the request. For example::
+
+            >>> c = Client()
+            >>> c.get('/customers/details/', {'name': 'fred', 'age': 7},
+            ...       HTTP_X_REQUESTED_WITH='XMLHttpRequest')
+
+        ...will send the HTTP header ``HTTP_X_REQUESTED_WITH`` to the
+        details	view, which is a good way to test code paths that use the
+        :meth:`django.http.HttpRequest.is_ajax()` method.
+
+    .. method:: Client.post(path, data={}, content_type=MULTIPART_CONTENT, **extra)
 
         Makes a POST request on the provided ``path`` and returns a
         ``Response`` object, which is documented below.
@@ -545,6 +556,8 @@ arguments at time of construction:
         Note that you should manually close the file after it has been provided
         to ``post()``.
 
+        The ``extra`` argument acts the same as for :meth:`Client.get`.
+
     .. method:: Client.login(**credentials)
 
         .. versionadded:: 1.0