Nebraska quarterback Dylan Raiola has a broken right fibula, sources told ESPN's Pete Thamel on Sunday, and will sit out the remainder of the season.
Raiola suffered the injury while being sacked and losing a fumble early in the third quarter of Saturday's 21-17 loss to USC.
After the game, Cornhuskers coach Matt Rhule told reporters that Raiola wanted to return to the game, but the sophomore couldn't run so Rhule decided it was unsafe to send him back in.
Raiola completed 10 of 15 passes against the Trojans for 91 yards and a touchdown before the injury. He was replaced by true freshman TJ Lateef, who went 5-of-7 for 7 yards and rushed for 18 yards on six carries.
Raiola had completed 72.4% of his passes for 2,000 yards and 18 touchdowns through nine games this season. He has been intercepted six times.
The Huskers (6-3, 3-3 Big Ten) lost their 29th consecutive game to an AP Top 25 opponent, a streak that dates to 2016. They will go on the road to face UCLA next Saturday.
ESPN's Max Olson and The Associated Press contributed to this report.