diff --git a/googleapiclient/_auth.py b/googleapiclient/_auth.py
index ada4ffb..9d6d363 100644
--- a/googleapiclient/_auth.py
+++ b/googleapiclient/_auth.py
@@ -120,6 +120,8 @@
 
 def apply_credentials(credentials, headers):
     # oauth2client and google-auth have the same interface for this.
+    if not is_valid(credentials):
+        refresh_credentials(credentials)
     return credentials.apply(headers)
 
 
@@ -128,7 +130,9 @@
             credentials, google.auth.credentials.Credentials):
         return credentials.valid
     else:
-        return not credentials.access_token_expired
+        return (
+            credentials.access_token is not None and
+            not credentials.access_token_expired)
 
 
 def get_credentials_from_http(http):
diff --git a/tests/test_http.py b/tests/test_http.py
index 9d48266..2109af7 100644
--- a/tests/test_http.py
+++ b/tests/test_http.py
@@ -71,6 +71,10 @@
     self._access_token_expired = expired
 
   @property
+  def access_token(self):
+    return self._bearer_token
+
+  @property
   def access_token_expired(self):
     return self._access_token_expired