He confirmed it on his blog:
The MRI I took yesterday told me that I tore my ACL after the high bar landing at the Japan Cup. Right now we’re in the process of scheduling a day to get it surgically repaired (hopefully sometime next week). While I’m definitely bummed about getting hurt, I’ve never thought to myself that going through all the injuries is not worth it. Gymnastics is a constant battle between pain and injuries and I do this sport because of that drive I have inside me to one day make the Olympic team.
For some reason, I see this injury as an opportunity in disguise. …
His club, Stanford University, made history this past season by becoming the first NCAA team to win the national academic team title and the NCAA team championship in the same year.
(both stories via Inside Gymnastics on Facebook)
Gymnastics Coaching.com 