Wisconsin starting quarterback Alex Hornibrook is going through concussion protocol and may miss Saturday's game at Northwestern.

Coach Paul Chryst told WIBA radio on Friday that Hornibrook is questionable for the game, and that sophomore Jack Coan would start in his place if the fourth-year junior cannot play. Chryst said the staff knew early in the week that Hornibrook might miss the game, and Coan has received extra work in practice.

"Jack has had really the week to start preparing and not knowing exactly when or if we'd get Alex, if he'd be cleared for this week," Chryst told WIBA. "Jack has had a lot of work."

Coan has yet to play this season, mainly because Wisconsin wants to capitalize on the new redshirt rule which allows players to retain a season of eligibility if they appear in four games or fewer. Coan appeared in six games as a freshman in 2017 and completed all five of his pass attempts.

Hornibrook is 25-5 as Wisconsin's starting quarterback and led the Badgers to a win over Illinois last week. He has 1,251 passing yards, 11 touchdowns and six interceptions this season.

Hornibook also suffered a concussion against Minnesota in 2016 and missed the Big Ten championship game. He started every game in 2017 and each of the first seven games this fall.