[Ingtar]

"when a runner is contacted by an opponent and touches the ground with any part of his body other than his hands or feet. The ball is dead the instant the runner touches the ground"

Ankle is considered part of the leg.

[where's_the_Outrage?]

If that’s the rule than I would agree it was the right call. What adds to the confusion is that it sounded like the booth announcer ref was saying the TD would be confirmed.

However, IMHO Michigan FUBAR’d the next play by not receiving the punt and letting the ball roll over 30 yards.