Brett Favre said he suffered a sprained throwing (right) shoulder in the first quarter of the Vikings' 38-14 victory over Buffalo on Sunday at Mall of America Field and will have an MRI on Monday.

However, coach Leslie Frazier said after the game that if Favre is healthy he will be the team's starting quarterback next Sunday when the Vikings play host to the New York Giants.

Favre, who started his NFL record 297th consecutive regular-season game on Sunday, said he has no idea if he will be able to extend that streak. Favre has battled through numerous injuries this year. He said the S-C sprain (sternum, clavicle) is a first for him in his 20-year career.

'The X-ray was negative," Favre said. "Nothing's broken, thank goodness. But I have no idea [if I can play next week]. ... I'm not concerned about that right now. We'll see what the MRI says tomorrow."

Favre was injured on a third-and-5 play on the Vikings' opening series when he scrambled right and was hit from behind by Buffalo linebacker Arthur Moats as he went to throw. Favre's pass popped up in the air and was intercepted by cornerback Drayton Florence.

Tarvaris Jackson replaced Favre, who eventually went to the locker room to be examined. Favre returned and remained in uniform but admitted he could not have thrown the football and only could have handed off with his left hand. Joe Webb, who is the Vikings third quarterback and was active for Sunday's game, suffered a hamstring injury in the opening half and was done for the day.

Jackson completed 15 of 22 passes for 187 yards with two touchdowns, three interceptions and an 85.0 passer rating. But Frazier made it clear there is going to be no controversy here.

"If [Favre's] healthy, he'll be our starting quarterback against the New York Giants," Frazier said. "Hopefully that will be the case but we'll wait and see what happens. But great job by Tarvaris. You don't want to take away from anything he did today. He had a great game."

Favre has said he will retire after this season.

Asked if he was worried he might have taken his last NFL snap, Favre said: "I don't know about worried. You're probably referring more to a streak or something like that. It's my 20th year. If I was a second year guy and we were talking about career that would be a concern. There's not many games left for me either way. I would like to see it through, I would like to play. It's what I came in here for. This is a different injury. I have no idea how I will respond to the week of treatment, so we will see."

Harvin stays home

Frazier said that wide receiver Percy Harvin was told to stay home Sunday rather than trying to come to the stadium. Harvin has been dealing with a migraine headache that started on Wednesday.

Harvin has dealt with the headaches since he was a youngster and this marked the second time he has missed a game because of the issue. The other time came last December when the Vikings played host to Cincinnati.

Frazier said he had an idea on Saturday that Harvin wouldn't be available. "I talked with him to get a feel for where he was," Frazier said. "We've had a good week of practice with the guys that were in there. It's important for us at this stage to figure out what we can do to help Percy. I feel bad for him. It's tough. ... We're going to try to do whatever we can to help him because he wants to play. He wants to be out there on the field but it's out of his control."

Safety sits to open game

Safety Madieu Williams was replaced by Tyrell Johnson in the starting lineup Sunday because he was late for the team bus after last week's game at Washington. Williams returned for the second drive.

"There are rules and regulations and I'm aware of it like everybody else," Williams said. "You have to abide by the rules and obviously I was late and that was part of the punishment."

Williams said he was late for the bus because he had numerous friends and family at the game and he was visiting with them. Williams is from the Maryland area.

A close call

Adrian Peterson rushed for 107 yards on 16 carries with three touchdowns Sunday,despite the fact he almost wasn't allowed to play because of a sprained right ankle suffered last week in Washington.

Peterson came on the field at about 10 in the morning to do some work with running backs coach Eric Bieniemy as Frazier, athletic trainer Eric Sugarman and others looked on. Afterward, Frazier, Bieniemy, Sugarman, vice president of player personnel Rick Spielman and offensive coordinator Darrell Bevell appeared to have a lively discussion about what to do.

After the game, Frazier said he came "real close" to shutting down Peterson.

"I told our team and Eric Bieniemy afterward that I can't believe that I was debating right until the last moment whether to play him or not, whether to dress him," Frazier said. "He kept telling me he thought he could go but when I watched him in the pregame I just wasn't certain and he's so valuable to our franchise, our team, our organization that you don't want to put him in harm's way. Adrian Peterson, there's only one like him. He's awesome. He's great. He did a great job."