MINNEAPOLIS -- Wearing a brace on his right knee and playing for the first time in three weeks, Adrian Peterson was a bit hesitant on the first few plays of the game.

"I definitely wanted to go out and get that first hit and see how it felt," Peterson said Sunday.

Once he took a few shots from the Detroit Lions, some of which he felt were cheap, Peterson was off and running. So were the Minnesota Vikings, 42-10.

The star rookie rushed for 116 yards and two touchdowns in less than three quarters of work and quarterback Tarvaris Jackson continued his steady improvement to lead the surging Vikings over the free-falling Lions.

"I got choked up a couple times, so it kind of pushed my buttons," Peterson said.

The favorite for Offensive Rookie of the Year showed he is back in a big way, but the Vikings suddenly appear much more than a one-man show.

In the last three weeks, Jackson has shown poise, an accurate arm and command of the offense that simply wasn't there early in the season, and Sunday was his best game yet. He was 18-of-24 for 204 yards and two touchdowns, and the Vikings (6-6) scored TDs on their first six possessions to win their third in a row and fourth in the last five games.

"We feel like we're getting on a roll and we want to stay on that roll," Jackson said.

The roll has the Vikings back in the thick of the NFC playoff picture, thanks in large part to a November swoon by the Lions (6-6) that has an all-too familiar feel for their long-suffering fans.

Jon Kitna threw for 260 yards and one touchdown for the Lions, who have lost four in a row to waste a 6-2 start. A month later, the Lions are looking more like the hapless Motor City Kitties who started the season with more losses than any team in the NFL over the last six years.

"Our boat's not very full, I know that. We don't have a lot of people left in our boat right now," Kitna said, referring to the sulking Lions locker room.

"I'm talking about us in general. We are not heading in the same direction right now, as a football team."

Coming in, the Lions talked about needing a sense of urgency to turn things around. But they showed nothing of the sort in a woeful effort.

The Lions rushed for just 23 yards on seven attempts against the league's top-ranked run defense, committed three personal fouls and were manhandled at the line of scrimmage.

"It's a team that's gotten tentative," said Lions coach Rod Marinelli, who blamed himself for the loss. "Today, especially, we looked lethargic. The fundamentals aren't being executed the way I wanted. ... And that's on coaching."

Peterson returned after missing two games with a torn lateral collateral ligament in his right knee. He looked to be just a step slower than his usual blazing self - but that was still two steps faster than the Lions' defense.

He ripped off a 28-yard run on the first possession to set up a touchdown run by Chester Taylor, then added a 16-yard scoring run to help the Vikings to a 14-3 lead.

The Lions came right back and scored on a 2-yard pass from Kitna to Casey FitzSimmons, but rookie Aundrae Allison returned the ensuing kickoff 103 yards for a touchdown to highlight a 28-point second quarter.

Jackson threw touchdown passes to Bobby Wade and Sidney Rice in the period, and the Vikings led 35-10 at halftime.

Peterson finished off the Lions on the first drive of the second half. He burst through a gigantic hole and then made safety Kenoy Kennedy look foolish with a paralyzing juke on his way to a 13-yard touchdown.

Taylor added 70 yards on the ground and the Vikings rushed for 216 yards.

Jackson said the Vikings were confident after watching Peterson in practice, but "we just wanted to see if he could get up after taking a shot."

The team as a whole took quite a roundhouse shot in a 34-0 loss at Green Bay a month ago that dropped it to 2-5. But just like their biggest offensive star, the Vikings are back up off the mat.

They moved into a tie for the final wild-card spot in the NFC, with games remaining at San Francisco, home against Chicago and Washington, and at Denver. But they may not have to worry about Detroit for that much longer.

Receiver Roy Williams left in the first half with a knee injury, and the Lions are in serious trouble.

"There's an easy way out and a hard way out," said Kitna, 13-25 lifetime in games played in December and January. "We have to choose the hard way if we want to do it. But we have to choose it - all 53 guys. We can't have some and not the others."

Notes

• Marinelli said Williams would be evaluated on Monday.
• Vikings S Dwight Smith was benched for the start of the game for disciplinary reasons. Vikings coach Brad Childress declined to elaborate.
• Childress has taken his fair share of criticism for being too conservative, but he emptied the playbook Sunday. Up 42-10, he called a fake field goal that got a first down, and then a halfback pass Visanthe Shiancoe dropped in the end zone.