Receiver Adam Thielen wasn't expected to play Thursday night against the Steelers after suffering a high ankle sprain just a few days ago, and the Vikings made it official on Wednesday.

Thielen and left tackle Christian Darrisaw were ruled out on the team's final injury report before the prime-time kickoff. Running back Dalvin Cook (shoulder) is listed questionable after two limited practices this week. Coach Mike Zimmer indicated Oli Udoh would remain at left tackle if Darrisaw still couldn't play after missing the Lions loss with a right ankle injury suffered in San Francisco.

K.J. Osborn is expected to start for Thielen. The second-year receiver replaced Thielen in the first series against the Lions and finished with four catches for 47 yards and a touchdown. Quarterback Kirk Cousins hasn't shied away from the 24-year-old Osborn.

"You always know [an injury] is a play away," Cousins said Tuesday, "but when it happens and you know you have somebody who can answer the call, it's a great sense of comfort at my position."

Thielen underwent an MRI earlier this week that determined he did not need surgery on his ankle, meaning he's expected to return at some point with at least four games left.

The Vikings' 30th-ranked defense will return three key defenders in cornerback Patrick Peterson and linebackers Anthony Barr and Eric Kendricks. Peterson was activated from the COVID-19 list on Tuesday after missing one game due to a positive test. Barr (hamstring/knee) and Kendricks (biceps), who missed the Lions game, will play after practicing fully on Tuesday and Wednesday.

Barr has missed 20 of the past 28 games. "I feel like I was playing pretty good up until I tweaked [the hamstring] against the 49ers," he said this week. "So it's one of those things where I have to figure out how to stay healthy and get back on the field."

Linebacker Blake Lynch (hip) and safety Camryn Bynum (ankle) are listed questionable.

For the Steelers, cornerback Joe Haden (foot), linebacker Robert Spillane (knee), left guard B.J. Finney (back) and defensive end Isaiah Buggs (ankle) have been ruled out.