Montgomery sustained a shoulder injury during Sunday's game at Indianapolis.
In the waning moments of the third quarter, Montgomery was seen walking to the locker room without a helmet or jersey, after which he was deemed questionable to return, per Nolan Bianchi of The Detroit News. Prior to his exit, Montgomery had eight carries for 37 yards and one touchdown and three catches (on three targets) for 36 yards. Jahmyr Gibbs should handle most of the backfield reps for the Lions for as long as Montgomery is sidelined.