Cook has been ruled out of Sunday's game against the Lions due to a knee injury.
On the first play of the Vikings' second possession after halftime, Cook galloped for 10 yards before going down with a non-contact injury to his left knee, per Courtney Cronin of ESPN.com. Cook immediately grabbed at his knee but was able to walk to the locker room under his own power. While the Vikings will surely touch on Cook's health in the aftermath of the game, Jerick McKinnon and Latavius Murray will head the backfield Sunday and perhaps beyond.