MINNEAPOLIS -- Dalvin Cook walked off the field and headed to the Minnesota Vikings' locker room with a noticeable limp in his step and a look of frustration on his face.
The rookie running back suffered a noncontact knee injury early in the third quarter Sunday against the Detroit Lions, and Vikings coach Mike Zimmer said the team is concerned Cook may have injured his ACL. Cook is set to have an MRI on Monday. He took a carry up the middle for 10 yards, and upon cutting to his right to avoid Lions safety Tavon Wilson, he reached for his left knee and fumbled.
Cook was tended to on the field by trainers and ruled out for the remainder of the Vikings' 14-7 loss to the Lions within minutes of disappearing into the locker room.
The Lions recovered the fumble at Minnesota's 29-yard line. Five plays later, Detroit took control with Ameer Abdullah's 3-yard rushing touchdown and followed up with a two-point conversion.
Cook was the only Vikings player to reach the end zone -- on a 5-yard run in the second quarter -- and finished with 66 yards rushing and 8 receiving.
What it means: The Vikings' string of bad luck with noncontact knee injuries continues. Teddy Bridgewater has been out for more than a year after going down in the 2016 preseason. They have been without Sam Bradford since he suffered a noncontact injury to his left knee during the Week 1 win over the New Orleans Saints. The severity of Cook's injury is unknown for now, but any prolonged absence by the explosive rusher could significantly dent the Vikings' offensive prowess. Cook has been the Vikings' do-it-all threat as a rusher, pass-catcher and in pass protection. If Cook misses time, it'll be up to Latavius Murray and Jerick McKinnon, who left the game with an ankle injury in the fourth quarter, to shoulder the load.
What I liked: The defense played its guts out. Unlike last week, the Vikings defense was on the field for 36:27, bailed out the offense after the first turnover and held the Lions to two field goals before Cook's injury. Minnesota applied constant pressure on Matthew Stafford, registering six sacks on the Lions quarterback.
What I didn't like: The third quarter was when everything went downhill, and that was before Cook's injury. The Vikings' offense opened up the second half on the good end of a 21-yard defensive pass interference call that got them to their own 47-yard line. A botched handoff between McKinnon and Cook out of the wildcat was the first turnover of the quarter. The Minnesota defense swooped in to pull out another stop, but then Cook's fumble resulted in Detroit's scoring drive. The two remaining drives for the offense in the third quarter resulted in a punt and a missed 39-yard field goal by Kai Forbath that bounced off the upright.
Fantasy fallout: Stefon Diggs connected with Case Keenum on big plays to spark momentum for the offense. Even when Keenum was under pressure, he was able to find Diggs down the sideline. The Vikings wide receiver finished with five catches for 98 yards.
Hunter makes a statement: The Everson Griffen-Greg Robinson battle paled in comparison to the work Danielle Hunter did against Rick Wagner. After a quiet start to the season, Hunter registered two sacks on Stafford in the first quarter and would have had a third had Linval Joseph not finished Stafford off.
What's next: The Vikings continue their three-game NFC North stretch at the Chicago Bears in Week 5, followed by the Green Bay Packers at home in Week 6. Zimmer has repeatedly said Bradford is "day to day," but the quarterback was not present for practice last week and there's still no word on when he will return. Minnesota is now bracing itself for the worst with Cook's injury. If the running back is out for a prolonged period of time, things could change significantly for the offense. "Dalvin’s a really explosive player, and he has such great big-play ability," Zimmer said. "We’ll have to look at things differently. If you lose a guy like him, you lose a lot of firepower."