That was probably the most gruesome hit I've ever seen (up there with Will Allen (OSU) on Willis McGhee (Miami) in the 03 national championship game and Garrison Hearst awful injury in 1998.
I hope he recovers. I've had a long/hate relationship with Knox. I think he's good at what he does well, but isn't physical enough to be a number 1 guy, but thankfully Marshall will take over that spot.