Detroit Lions running back David Montgomery is out indefinitely after suffering an MCL injury during a 48-42 loss to the Buffalo Bills on Sunday, according to ESPN's Adam Schefter.
Ian Rapoport of NFL Network reported additional details:
Schefter noted that Montgomery is undergoing additional testing on his knee, but he "could be lost for the season."
Detroit has been hit hard by injuries recently, as defensive tackle Alim McNeill suffered a season-ending torn ACL while cornerback Carlton Davis will be sidelined for six weeks with a fractured jaw (via Rapoport).