MINNEAPOLIS — Minnesota Vikings running back Dalvin Cook’s availability this week for the game at winless Detroit is in doubt because of an injury to his left shoulder, but coach Mike Zimmer stopped short on Monday of confirming a long-term absence.

Cook was hurt on a carry late in the third quarter on Sunday at San Francisco and carted off in obvious pain. Zimmer said Cook did not sustain a torn labrum, an injury he had to the other shoulder two years ago, and did not rule out him playing against the Lions.

“It’s day to day. That’s what they’re telling me,” Zimmer said.

Cook has 773 rushing yards, 202 receiving yards and four touchdowns in nine games. He missed two games earlier this season with a sprained ankle, and his average of 4.5 yards per rush is the lowest of his five years in the league.

The Vikings are 15th in the NFL in rushing yards per game, down from fifth and sixth the past two seasons. Zimmer said he didn’t think Cook’s health has negatively affected the team’s productivity.

“We haven’t been able to get to some of the backside runs quite well enough, or get them reached to the perimeter, so we’ve just got to keep working to try to look at some of those,” Zimmer said.

Cook sat out the last two games in 2019 with a shoulder injury he tried to play through but admitted was adjusting his falls at the end of runs to avoid landing on the joint and exacerbating the pain. He returned for the playoffs and had 130 yards from scrimmage and two touchdowns in the wild-card round win at New Orleans.

The Vikings also placed cornerback Patrick Peterson on the COVID-19 reserve list on Monday. He’ll need two negative tests in time to play at Detroit.

“Not too many guys have passed those two negative tests, so you just have to let it play out and see where it goes,” Zimmer said.

Defensive tackle Dalvin Tomlinson had his first career NFL absence on Sunday, because of COVID-19. His status for this week is not yet clear.

The Vikings have two starters out with season-ending injuries: defensive end Danielle Hunter and tight end Irv Smith. Nose tackle Michael Pierce (elbow) has missed seven games and counting.

Defensive end Everson Griffen will be out indefinitely on the non-football illness list while he’s in psychological treatment following a frightening episode that played out at his home last week.