Zaire's ankle got caught under a Cavaliers defender during a run, with the No. 11 Fighting Irish up 19-14 late in the third quarter. He was carried to the sidelines and eventually put on a cart.
Zaire underwent X-rays, the results of which have not yet been made public, at the Scott Stadium facilities, according to the ABC broadcast. His mother and her husband were also summoned to the locker room.
Zaire was not wearing an air cast when he was carted off.
Notre Dame coach Brian Kelly said in his postgame interview following his team's 34-27 win that the initial prognosis "wasn't great news," but that he didn't know the extent of the injury, and would find out more in the locker room.
The redshirt sophomore quarterback was making his third career start. He had completed 7 of 18 passes Saturday for 115 yards and a touchdown, while rushing 10 times for 87 yards.
Kizer finished with 92 yards and two touchdowns on 8-of-12 passing, including a 39-yard go-ahead strike to wide receiver Will Fuller to silence the Cavaliers' comeback bid.