EDEN PRAIRIE, Minn. — As the Minnesota Vikings plunged into a second week of uncertainty at their most important position, quarterback Sam Bradford offered reasons to believe he’ll return swiftly from a left knee injury.

That’s the hope at team headquarters and among the fan base, at least, following a 26-9 loss at Pittsburgh with backup Case Keenum forced into action .

As for the chance Bradford will be able to play on Sunday against Tampa Bay and keep his absence to one game?

“I would like to think that they’re good, but a lot just depends on how my knee responds when we go out there and practice this week,” Bradford said Wednesday before taking the field.

The Vikings listed him as a limited participant in the workout, as they did each day last week, but the soreness and swelling in Bradford’s twice-repaired knee didn’t improve enough by pregame warmups to gain clearance to play against the Steelers. Bradford had reconstructive surgery while with St. Louis in both 2013 and 2014 after tearing his anterior cruciate ligament each time.

“After the two ACLs, there have been some ups and some downs with it, but this particular issue I’m not sure I’ve ever dealt with this before,” Bradford said.

While posting a career-best 143.0 passer rating with a brilliant performance in the season-opening 29-19 victory over New Orleans on Sept. 10, Bradford twisted the knee in a non-contact situation. Though he showed no sign of trouble and never felt concern, the knee caused him increasing discomfort as the night went on. The next morning was worse. Taking it easy throughout the week wasn’t enough.

“I was hoping that it was going to feel better than it did,” Bradford said.

Neither the Vikings nor Bradford have revealed specific details of the nature of the injury, though occasional soreness and swelling in a knee that has been previously reconstructed is not abnormal. Asked whether this could be a chronic issue he will have to manage moving forward, Bradford said he wasn’t sure.

“I think we’ll figure that out kind of as we go, to be honest,” he said. “Hopefully it will continue to get better each day.”

That’s been the message from frustrated coach Mike Zimmer, too.

When asked if he’s confident Bradford will play against the Buccaneers, Zimmer responded: “It’s day to day. How do I know?”

Zimmer was at least upbeat about Keenum’s previous NFL experience and energy on the field, even if his performance against the Steelers left a lot to be desired. Keenum didn’t throw any touchdown passes and struggled at times in the face of an aggressive pass rush, but he didn’t commit any turnovers, either.

“When you see him out there in a game, you see that desire and burn that he has deep down,” tight end Kyle Rudolph said. “He wants to go out there and make plays for us and help us win.”

Undrafted out of Houston, Keenum stayed in the same city to start his professional career with the Texans. Then he spent the next two years with the Rams. His overall record as a starter is 9-16.

“I’m ready for whatever. I don’t think anything in this league surprises me anymore, even though there are some surprising things that always happen,” he said.


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