For general information: Back on their 'a day' nonsense, I was in Auburn. The Auburn Mall also ran shuttle service to and from the stadium. I'm assuming this same service will be available for game day. This shuttle run will be significantly longer than Y beach. I'm guessing 15 min no traffic. Probably 30-40 minute game day travel time, unless they set up a shuttle only lane?? But for visitors it can be beneficial?
To see if this is a viable option for yourself, go to google.com/maps and get directions from Auburn Mall to Auburn.