After just four games, Dalvin Cook's rookie season is already over. 

Vikings coach Mike Zimmer announced on Monday that Cook will miss the rest of the 2017 season after tearing his ACL in Minnesota's 14-7 loss to the Lions on Sunday.

Cook, who's been one of the most electrifying rookies in the NFL this year, suffered the injury on a non-contract play in the third quarter. After taking a handoff from Case Keenum, Cook exploded up the middle for a big gain. On the play, the Vikings rookie somehow injured his knee as he was trying to make a cut to the right to avoid Detroit's Tavon Wilson. 

Before leaving the game with the injury, Cook had averaged an impressive 5.1 yards per carry against the Lions defense (13 carries, 66 yards). 

"I talked to him after the game," Zimmer said on Monday, via the team's official website. "He's a great kid, I'm extremely impressed with everything that he's done to this point. It's obviously a terrible thing for him and for us. He's a great worker and I have no doubt that he'll come back from this."

Zimmer also said that he expects Cook to undergo surgery at some point in the next few days. 

"He has to wait until the swelling goes down and then he'll have it done," Zimmer said. "I expect him to come back and be the same as he was."

Cook won't be easy to replace, and that's mainly because he's been carrying the load for the Vikings offense this year. The rookies' 354 yards rushing ranked third in the NFL through four weeks and was quadruple the rushing yards of every other Vikings player combined. 

The loss of Cook means that Latavius Murray, who carried the ball seven times for 21 yards against Detroit, will likely get the call to be Minnesota's featured back. 

"He said he's ready to go and we're ready to have him go," Zimmer said. 

For Zimmer, this probably almost seems like deja vu. This is the second year in a row that he's watched both his quarterback and running back suffer serious injuries. In 2016, Teddy Bridgewater and Adrian Peterson spent most of the season on the sideline after suffering serious injuries. 

This time around, the Vikings will be missing Cook, and they're also missing Sam Bradford, who's been dealing with a knee problem that has caused him to miss the past three games. Zimmer has been vague about when Bradford might return, which means the Vikings quarterback could be back on the field in Week 5 or he could miss several more weeks.