Wednesday was the deadline for the Vikings to decide Bridgewater's status for the rest of the 2017 season. He spent the first six weeks on the physically unable to perform list, was medically cleared to return to practice on Oct. 18, and the Vikings then had a three-week window to determine whether Bridgewater was ready to play this season.
In order to make room for Bridgewater on the 53-man roster, the Vikings placed veteran quarterback Sam Bradford on injured reserve, thus shutting him down for the rest of the regular season. If the Vikings make the playoffs and Bradford is healthy, the team could elect to activate him off IR at that point.
"It's disappointing," Vikings coach Mike Zimmer said of Bradford going on IR. "The guy worked extremely hard to try and get back. He spent a whole bunch of his own money trying everything to get back, and it just didn't work out. Hopefully we'll be able to get him back when he gets healthy."
Zimmer said Keenum will remain the starter when the Vikings face the Redskins on the road in Week 10, and Bridgewater is expected to serve as his backup. Bridgewater has not experienced any medical setbacks since rejoining the team in practice three weeks ago to lead the scout-team offense.
The Vikings expect Bridgewater to transition back to his starting role when needed, sources told ESPN.
"Just trying to get him up to speed as fast as possible," Zimmer said Wednesday. "... When he was rehabbing, before he started practicing, he was throwing to nonreceivers, but since then he's been pretty good. There might have been one day he was a little rusty, but for the most part I thought he's thrown the ball well."
For weeks, Bradford has battled side effects of a noncontact knee injury he suffered when he led the Vikings to a 29-19 win over the Saints in Week 1. Bradford underwent an arthroscopic procedure Tuesday in which Dr. James Andrews "cleaned up" the left knee but found no major damage, team sources told ESPN's Chris Mortensen.
Initial tests conducted the first time Bradford visited Andrews in September revealed no structural damage, but inflammation continues to be the root of the quarterback's pain management issue. Bradford sought out other options and received unsuccessful treatments in October in hopes of reducing the pain and inflammation.
Bradford appeared in one other game in the Vikings' Week 5 win at Chicago, where he had to be removed with 25 seconds remaining in the first half because of pain.
"It was just lingering," Zimmer said of the decision for Bradford to have surgery. "We thought it was going to be a one-week deal, then it was two, then it was three, and then it was eight. Nothing else was working. We had to try something."
Bradford, who turned 30 on Wednesday, will become an unrestricted free agent next season. He'll earn $18 million in 2017 from the Vikings with a $14 million base salary and a $4 million roster bonus.
"He is a great person, heck of a quarterback," Zimmer said. "We don't know where he's at with his knee. I haven't talked to him about anything about next year. We're just thinking about this year. I love the kid. Great kid, great competitor. It was disappointing we had him for one game, but that's life."
Bradford appeared in 17 games with the Vikings after being traded from Philadelphia for a first- and fourth-round draft pick when Bridgewater suffered a major noncontact knee injury while running a drill in practice on Aug. 30, 2016. Bridgewater was rushed to a Level 1 trauma hospital out of fear that he could lose the lower part of his leg after dislocating his knee and tearing multiple ligaments, including the ACL.
Bradford has a 9-8 record as a starter in Minnesota and has thrown 23 touchdowns to five interceptions with a 71.8 completion percentage.
While Sloter has yet to play a down in 2017, sources confirmed the Vikings did not want to risk losing him by releasing him to the waivers market. From Week 8 on, all players cut go directly to waivers. In Sloter's case, it would have been difficult for the Vikings to sneak him through the waiver wire and sign him to the practice squad before a quarterback-needy team scooped up the rookie's talents.
Bridgewater's last non-preseason action came during the 2015 season, when the Vikings lost to the Seahawks in the NFC wild-card game on Jan. 10, 2016. His 3,231 passing yards that season earned him an invite to the Pro Bowl.
He threw for more yards than any Vikings quarterback during their first two seasons. Bridgewater has the highest completion percentage (64.9) of any quarterback in his first two seasons in NFL history.