diff --git a/lib/omniauth/strategies/google_oauth2.rb b/lib/omniauth/strategies/google_oauth2.rb
index 68f0cf1..010ce8f 100644
--- a/lib/omniauth/strategies/google_oauth2.rb
+++ b/lib/omniauth/strategies/google_oauth2.rb
@@ -2,7 +2,9 @@
 
 module OmniAuth
   module Strategies
-    class GoogleOauth2 < OmniAuth::Strategies::OAuth2
+    class GoogleOauth2
+      include OmniAuth::Strategy
+
       option :client_options, {
         :site => 'https://accounts.google.com',
         :authorize_url => '/o/oauth2/auth',