diff --git a/vendor/golang.org/x/oauth2/token.go b/vendor/golang.org/x/oauth2/token.go
index ee4be54..8227203 100644
--- a/vendor/golang.org/x/oauth2/token.go
+++ b/vendor/golang.org/x/oauth2/token.go
@@ -154,7 +154,7 @@
 // This token is then mapped from *internal.Token into an *oauth2.Token which is returned along
 // with an error..
 func retrieveToken(ctx context.Context, c *Config, v url.Values) (*Token, error) {
-	tk, err := internal.RetrieveToken(ctx, c.ClientID, c.ClientSecret, c.Endpoint.TokenURL, v)
+	tk, err := internal.RetrieveToken(ctx, c.ClientID, c.ClientSecret, c.Endpoint.TokenURL, v, internal.AuthStyle(c.Endpoint.AuthStyle))
 	if err != nil {
 		if rErr, ok := err.(*internal.RetrieveError); ok {
 			return nil, (*RetrieveError)(rErr)