Brett Favre might have missed a few weeks of the preseason but it won't take him much time before he's put into a game.

Coach Brad Childress said Friday the quarterback will play a series or possibly two -- depending on how long the first series runs -- on Sunday night as the Vikings play the 49ers in San Francisco in a game that will be televised nationally by NBC.

Childress said ideally the first series would go 10 plays for Favre because, "that's what he needs right now and all he's ready for right now."

"I think he's doing a good job of rounding into," form, Childress said. "He has been throwing the football, there is no question about that. Just conditioning his legs. ... He's versed in our system and our calls."

Tarvaris Jackson will take over for Favre and play past halftime and then be replaced by Sage Rosenfels. Childress said he does not know if rookie Joe Webb will be able to get in the game. The rest of the first-team offense will play the opening quarter.

Middle linebacker E.J. Henderson, who suffered a fractured femur last December, will make his first appearance this preseason and play with the defensive starters in the first quarter. Asher Allen will start at right cornerback and then will rotate on a series-by-series basis with Lito Sheppard. Childress said that Antoine Winfield will start at the left corner but only play one series before being replaced by rookie Chris Cook.

Winfield is coming off a broken foot and although he appears to be completely healthy the Vikings certainly want to get more of a look at Cook, who has impressed in the preseason.

Harvin returns

A day after giving everyone a scare when he collapsed on the practice field, Percy Harvin returned to Winter Park and was on the sideline for the start of practicing wearing shorts and a shirt. He was greeted by several of his teammates and also talked to Childress and vice president of player personnel Rick Spielman.

Although Harvin was believed to be suffering from another bout with migraine headaches when he collapsed, Childress said Harvin will continue to undergo precautionary tests over the weekend and won't make the trip to San Francisco.

Childress does not know how long Harvin will be held out. "He could have probably come over here and done some things today except for the fact that they have a couple of tests that they want to finish with," Childress said. "I don't know that we're going to solve that riddle immediately and I don't think there are any quick fixes and I think it's just going to be a work in progress. You'd like to stick it in a box and have it be fixed this way. History has told us that migraines aren't that way so we'll try to take all the knowns out of it. The testifying is trying to disqualify [things]."

Asked if he had to start looking at weeks where Harvin was OK to go as simply a bonus, Childress said: "I don't know. I don't know how I'll end up looking at it. He had a few last year that he dealt with and we dealt with. If it was his first choice he'd be here for all the prep for every week. But the fact is he has played and played well in games that he's had a migraine the week of the game. It's just a matter of is it a short one, a hard one, a two-day one and then what he was able to get out of the game plan?"

Vikings look at Walker, Jones

Childress confirmed the Vikings put wide receivers Javon Walker and Brandon Jones through workouts this morning. Walker had most recently been with Oakland and Jones with San Francisco.

Childress, asked about the concern of depth at wide receiver with Harvin and Sidney Rice (hip) being out and Jaymar Johnson being waived/injured, said: "We're not going to keep all the guys that we have right now. We'll just see how it goes going forward. There are able-bodied guys. We are checking the other able-bodied guys out there that we feel like are a fit for us here."

The Vikings planned to give Walker and Jones physicals and then Childress will meet with them. We should find out later today if either signs. Walker is an interesting possibility because he's familiar with both Favre and offensive coordinator Darrell Bevell from their time together in Green Bay.

Walker had his best season with Favre as his quarterback in 2004, catching 89 passes for 1,382 yards and 12 touchdowns. All were career highs. Of course, Favre and Walker also had their rough patches. See this item from Pro Football Talk.

Other notes from Friday:

  • Rice said he felt some pain Friday as he tried to push it while running and said it's now up in the air whether he will be ready for the Sept. 9 opener at New Orleans.
  • Center John Sullivan (calf) won't make the trip to San Francisco for Sunday's game but Childress expects him to be back on the practice field Tuesday. Sullivan has missed much of camp after suffering what looked like a nasty cut on the back of his leg on the second day of practice. "We're just trying to settle that thing down as far as we can," Childress said.
  • Asked about the Yahoo! Sports report in which sources said Favre and many players have no respect for Childress, the coach said: "I don't know that much about journalism. I know that most people write with a source. You can ask Brett aboout that. I'm probably biased in how I look at it. You can ask anybody on our football team. That's you guys. How do I look at it? You don't like it but you deal with it. You sit at the top, everybody knows who they are shooting at. So they can say whatever they want to say and make an argument for it."
  • Wide receiver Bernard Berrian had the quote of the day when asked about the distractions the Vikings have faced of late: "Nah, I mean it's not distractions. It's the same thing as last year. I don't see why it would be any more distractions than it was last year. ... I think we're the best conditioned team on distractions, beside Cincinnati."
  • The Vikings began practice outside but moved inside when it began to rain and thunder was heard at one point.
  • Tight end Garrett Mills, who has battled injuries throughout his career, appeared to injure his right knee during a 7-on-7 drill. Mills left the field and went to the locker room.
  • Cornerbacks Lito Sheppard and DeAndre Wright returned to practice.