The University of Michigan fired its head football coach "with cause", effective immediately, the school announced in a statement on Wednesday.
The university said an investigation found "credible evidence" coach Sherrone Moore had "engaged in an inappropriate relationship with a staff member".
The same day he was fired, Mr Moore was detained by police in a nearby suburb for alleged assault, according to police statements obtained by ESPN.
His termination represents the latest shakeup in the billion-dollar world of college sports, after Lane Kiffin announced last week that he was leaving the University of Mississippi to coach at Louisiana State University under a $91m contract.
Like coach Kiffin's, Mr Moore's exit from the team occurred on the eve of the College Football Playoff and a slate of championship games referred to as bowl games.
