diff --git a/google/oauth2/challenges.py b/google/oauth2/challenges.py
index c0a335b24..5ae7ebf15 100644
--- a/google/oauth2/challenges.py
+++ b/google/oauth2/challenges.py
@@ -25,7 +25,7 @@
 
 
 REAUTH_ORIGIN = "https://accounts.google.com"
-SAML_CHALLENGE_MESSAGE = "Please run `gcloud auth login --update-adc` to complete reauthentication with SAML."
+SAML_CHALLENGE_MESSAGE = "Please run `gcloud auth login` to complete reauthentication with SAML."
 
 
 def get_user_password(text):