It's Sunday morning, and the Minnesota Vikings now know who will be starting at quarterback for their Week 2 game against the Pittsburgh Steelers. Starter Sam Bradford tested out his injured knee Sunday morning and the team has decided not to risk his health, and will instead start backup Case Keenum, according to CBS Sports NFL Insider Jason La Canfora. 

Bradford had an MRI on his knee earlier this week, and the Vikings responded by signing a practice squad quarterback to the active roster in case he's forced to miss the game. Mike Zimmer, asked about Bradford's status, responded, "I'm not going to talk about who's had MRIs or who hasn't had MRIs," per StarTribune.com. "Lots of guys have MRIs. I had one, two maybe, on my knee."

The team did not seem overly concerned, and expected Bradford to possibly play, but reporting from NFL Network's Ian Rapoport shed light on just how up in the air the situation is. "It doesn't sound like they're too concerned with Sam Bradford," Rapoport said Sunday morning on NFL Network. "He's a little banged up. Had an MRI, had some tests. It did not reveal any structural damage, but the problem is he's had a lot of structural damage on that knee, so the actual MRI and what they found may be hard to decipher. Of course, he's had two [torn] ACLs. But they do think Sam Bradford is going to be on the field and playing, this just might be something he needs to kind of work with and deal with some maintenance on over the next couple weeks."

Obviously, it was more difficult for Bradford to get on the field this week than the team initially expected. It's a big blow for a Vikings offense that looked excellent last week, with Bradford throwing dimes all over the field against the New Orleans Saints. Keenum will likely take his place under center for as long as he's out, unless and until Teddy Bridgewater comes off the physically unable to perform list, which he is not eligible to do until after six games.