Minnesota Vikings quarterback Sam Bradford is inactive with a knee injury and will miss Sunday’s game against the Pittsburgh Steelers.

Case Keenum will start for Minnesota. Keenum started nine games for the Los Angeles Rams last season.

After early warmups on Sunday, Bradford’s prospects for playing took a big hit. The first overall pick in 2010 threw several hours before game time at Heinz Field but didn’t move much or drop back at all on his balky left knee, per several reports.

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Bradford, who is officially listed as questionable, has suffered several injuries throughout his career: Two torn ACLs headline the list, but he’s also dealt with shoulder, ankle and concussion issues. Luckily, the team announced that with this injury, there is no structural damage.

It’s a disappointing turn for Bradford, especially after a monster performance in Week 1. Playing in front of a national audience on “Monday Night Football,” the former Oklahoma Sooner sliced up the New Orleans secondary, completing 27 of 32 passes for 346 yards in a convincing 29-19 win. He tossed three scores: two to Stefon Diggs and one to Kyle Rudolph.

Keenum threw for nine touchdowns and 11 interceptions before losing the starting gig to Jared Goff. Keenum is 9-15 in 24 career starts spanning across Houston, St. Louis and Los Angeles.

The Vikings also activated Kyle Sloter this week, and he will serve as the primary backup.

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