Cook (shoulder) was estimated as a non-participant Monday in the Vikings' walk-through practice.
Vikings head coach Mike Zimmer hasn't been willing to put a timeline on Cook's return from the dislocated left shoulder he sustained in the Week 12 loss to the 49ers, with Zimmer merely labeling the running back as day-to-day. After sitting out the Vikings' Week 13 loss to the Lions and having yet to get back on the practice field, Cook would seem to face an uphill battle to gain clearance for a Thursday matchup with the Steelers in Week 14. If that's the case, Alexander Mattison would be poised for a second straight turn as Minnesota's lead back.