The team's fear of a torn ACL in the rookie running back's left knee was realized Monday, sealing the end of a promising rookie season.
Coach Mike Zimmer confirmed the diagnosis, signaling the switch to Latavius Murray as the primary ball carrier. Cook will have reconstructive surgery once the swelling subsides. Some additional cartilage damage was discovered, Zimmer said, but no additional ligaments were injured beyond the ACL.
"He's a great kid," Zimmer said. "I'm extremely impressed with everything he's done to this point. It's obviously a terrible thing for him, and for us, but we'll move forward and go on from there. He's a great worker, and I have no doubt that he'll come back from this."
Cook was injured trying to cut for more yards near the end of a run in the third quarter of Minnesota's defeat by Detroit on Sunday . He lost a fumble on the play and needed help off the field. Afterward, he was on crutches, wearing a bulky brace.
"I'm praying for him," Murray said. "I told him I care about him, more than anything, that he's all right."
Cook endured some shoulder trouble in college at Florida State, but this will be a new challenge. Not so for the Vikings, who are essentially still recovering from the dislocated left knee suffered by quarterback Teddy Bridgewater last year and the domino effect it had on the roster.
Bridgewater remains on the physically unable to perform list. His replacement, Sam Bradford, has missed three straight games because of a sore left knee. Several other starters on the offense in 2016 went down with season-ending injuries that left scars on the team psyche.
They haven't completely faded.
As much as the stay-the-course mindset is preached around the league, necessitated by the injury-dominated sport with a 16-game schedule, Vikings players and even Zimmer acknowledged to feeling some frustration about the latest setback since the end of the 14-7 loss to the Lions.
"It shows what kind of team you are when you just fight through that and keep playing," wide receiver Adam Thielen said, "and hopefully we can get things together and start winning games."
Just when the Vikings offense was showing some balance and potency that wasn't there last year, with a vastly improved offensive line run blocking and pass protecting with a command and consistency largely unseen in 2016, the most dynamic player has been cruelly removed from action .
"Dalvin had unbelievable big-play ability in a lot of different ways," Zimmer said.
With 354 yards, Cook is third in the NFL in rushing. He has two touchdowns, plus 11 receptions for 90 yards for the Vikings (2-2), who play at Chicago next Monday. Jerick McKinnon will likely have his role expand along with Murray, but the Vikings might have to sign another veteran running back, too.
"We're looking at everything," Zimmer said.
Murray, in his first season with the team after leaving the Oakland Raiders, was limited through training camp as he worked his way back from surgery on his right ankle. Murray, who had seven carries for 21 yards after Cook left, said on Monday he still doesn't think he's 100 percent recovered.
"But I feel good enough to be out there and I'm confident in myself that I can play at a high level," Murray said.
While the Vikings start work on keeping their season afloat, Cook will turn his attention to recovery and rehabilitation. He'll have the benefit of Vikings head athletic trainer Eric Sugarman and his staff, a group that has helped steer many a player back from significant injuries. Adrian Peterson, Cook's predecessor at running back, is the most famous of the comeback stories. He was carrying the ball in the 2012 opener less than nine months after tearing his left ACL.
Zimmer made sure to point this out to Cook in their conversations after the injury.
"I expect him to come back," Zimmer said, "and be the same as he was."
As for Bradford, well, his status is officially still in the nebulous day-to-day category. Whether Bradford or Case Keenum plays against the Bears is still unclear.
"Everything he is doing is feeling better," Zimmer said. "But obviously, we don't know."
Though he's not going to replace Cook, the Vikings at least can add another potential big-play piece to the offense this week with the return of wide receiver Michael Floyd from his four-game suspension. He's more than ready to be done watching.
"It's kind of nerve-wracking. Obviously you want to be out there and play," Floyd said. "But you just sit back, let the time fly. I'm excited to be back."
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