Will miss time with knee sprain

Head coach Matt Nagy said Wednesday that Montgomery will "miss some time" with a knee sprain, Larry Mayer of the Bears' official site reports.

Nagy didn't get into specifics regarding a recovery timeline for Montgomery, but Dan Graziano of ESPN.com reported Tuesday that the running back would likely miss four or five weeks. With Nagy confirming that Montgomery will be sidelined, the Bears have Damien Williams (thigh) and Khalil Herbert as backfield options on the active roster for Week 5 at Las Vegas. Chicago also has Artavis Pierce and Ryan Nall on the practice squad, while Tarik Cohen (knee) is on the PUP list through at least Week 6.