Oh sure, he was fast, elusive and just about impossible to catch, but Chicago Bears nose tackle Dusty Dvoracek wasn't talking about what happened the last time the Minnesota Vikings visited Soldier Field. He was recalling their time at Oklahoma.

"He was always kind of banged up, (the coaches) never wanted to get his shoulders hurt," Dvoracek said. "So no banging on Adrian."

Of course, to hit him the Sooners had to catch him.

The Bears learned just how difficult that can be last year when Peterson ran wild in a 34-31 victory at Soldier Field, and will try to avoid a repeat when the Vikings visit on Sunday.

He carried 20 times for 224 yards on that mid-October day, a club record he broke again three weeks later at San Diego and the most yards rushing ever allowed by the Bears. He ripped off runs of 67, 73 and 35 yards while running around the end, through the middle or crisscrossing the field.

If that wasn't enough, he also set up Ryan Longwell's winning 55-yard field goal by returning a kickoff 53 yards.

"I really can't explain," Peterson said. "We just did a great job on offense executing. Those guys did a great job making blocks. It led to some big plays."

It added up to a 60-minute highlight reel, and the Bears don't need to review it to understand they can't let him do that again.

"We just have to stay gap sound and tackle him," defensive end Alex Brown said. "You don't want one guy trying to tackle him. He's a big dude, runs hard and runs like he's mad at somebody."

The Bears did a better job in the rematch at the Metrodome in December, holding him to 78 yards, and they'll need more of the same Sunday. Both teams are 3-3 and tied with Green Bay atop the NFC North with a bye week approaching, and both made some big changes on offense since last year.

Kyle Orton beat Rex Grossman for the Bears' starting quarterback job and is eighth in the league with 1,386 yards passing.

Bernard Berrian is now catching long balls for the Vikings instead of the Bears after signing a six-year deal in the offseason, and veteran Gus Frerotte replaced the young and ineffective Tarvaris Jackson at quarterback.

Suddenly, there's life in the passing game.

Berrian caught five passes for a career-high 131 yards, including an 86-yard touchdown, in last week's 12-10 win over Detroit - his second straight 100-yard game. Frerotte is 3-1 as a starter and has passed for at least 204 yards in each outing, including 296 against the Lions.

"When you have a receiver that can make really good plays for you, you're going to try and get him the ball whether it's by game plan or looking for him in certain situations," Frerotte said. "For me, I try to have the trust of all the guys who are going to get the ball, whether it's a running back, tight end, a receiver, whoever it is."

Now, they're looking at an opponent that ranks 27th against the pass, with a banged-up secondary.

Nathan Vasher has missed two straight games with an injured right wrist, and Charles Tillman left last week's 22-20 loss to Atlanta with an injured left shoulder, meaning both starting cornerbacks might not be available Sunday. Trumaine McBride injured his left shoulder and nickel back Danieal Manning pulled a hamstring, too.

That could bode well for the passing game, but the offense still revolves around the run.

Peterson had already had rushed for more than 100 yards in three of his first four games before delivering a performance that opened eyes around the league in his last visit to Chicago.

"Guys started focusing on stopping the run," he said. "That's when as a running back we started seeing a lot of different defensive fronts and defensive looks coming at us to try and keep the running game under control."

Three weeks later, Peterson trumped that by running for 296 yards against San Diego. By the time the season was over, he had 1,341 yards despite missing two games and was voted Offensive Rookie of the Year and Pro Bowl MVP.

This year, he hasn't been quite as spectacular. He has been good, though.

He's third in the league with 563 yards and is averaging 4.4 per carry, down from 5.6 last year. He also has three fumbles after committing four a year ago.

On Sunday, he expects to see "a totally different team. Defense is playing different. They have guys back who are finally healthy."

One of those guys is Dvoracek, who missed the final 15 games last year with a torn anterior cruciate ligament in his left knee. And he has a free pass from the coach to take down Peterson - if he can catch him.

"It was always fun going against him in practice because we weren't keeping score. It was nice," Dvoracek said.