The United States defender told Chelsea's official website: "I haven't played at the Rose Bowl but it is one of those stadiums everyone knows. It is one of the biggest and some of the most historic football games are played there.
"Michigan is one of the biggest if not the biggest in the world. It's a college football ground, holding something like 107,000 people.
"I remember watching Man United and Real Madrid play there a couple of years ago and it was packed."