The focus when facing the Minnesota Vikings hasn't changed much for the Chicago Bears: Stop Adrian Peterson and Jared Allen.

Allen, who has seven sacks, beat Bears LT J'Marcus Webb for 3.5 sacks of Josh McCown in the 2011 season finale and beat Webb for a sack of Jay Cutler in the 39-10 Bears rout of the Vikings at Soldier Field. Of Allen's 112 career sacks, 13 came against the Bears and all were in his five seasons since coming to Minnesota from Kansas City. 

"Every time we drop back to throw the ball, he’s Waldo," offensive coordinator Mike Tice said. "We have to make sure we know where he is and find him and make sure we have an answer for that, without a doubt."

The Bears expect to chip block on Allen to help Webb.

"He knows it," Tice said.

Peterson's phenomenal return from major knee surgery in only about seven months would have resulted in the comeback player of the year award if he'd gained 500 yards at this point. But his league-leading 1,128 yards have him ahead of his career-best pace of 1,760 in 2008. 

"He's always a concern," coach Lovie Smith said. "Unfortunately, I've seen a lot of his best games from the other side of the field."

The 224-yard game Peterson had in 2007 comes to mind. It was the last time the Bears lost (34-31) at Soldier Field to the Vikings.

"I just think you have to be disciplined, in your gap," Smith said. "You've got to be ready to play, No. 1, be disciplined, read your keys and gang tackle. 

"I mean, that's what it's about, trying to get 11 guys to the ball as often as we can."

When Smith said Peterson had some of his best games against the Bears, he was speaking of ancient history in a league where yeterday means little. Peterson hasn't had a 100-yard game against the Bears since 2008. He had 39 yards in game last year and 51 in a 2010 game. 

Minor wounds: No players are expected to be sidelined Sunday, although there are some minor injuries. 

QB Jason Campbell (ribs), LB Lance Briggs (thumb), G Lance Louis (ankle), WR Brandon Marshall (shoulder), DT Stephen Paea (shoulder), DE Julius Peppers (thigh) and DT Matt Toeaina (calf) went through full practices Friday and have been listed as probable on the injury report. TE Kellen Davis has had one limited practice this week due to an ankle injury and is questionable. Earlier in the week, DE Shea McClellin received his go-ahead from an independent neurologist following a concussion that kept him out of almost two full games.

Informal apology: Marshall did a lot of talking on the sideline and in the embarrassing loss Monday, and realized he got carried away. He offered up somewhat of an apology and explanation.

"It would be very disappointing if we don't make a run for it now," he said. "So I have a sense of urgency about myself right now, just playing better, making all of my plays, being a better teammate. 

"When I look at film I let some frustration out, and I need to do a better job of that. But with that being said, we're still in a good place."

Follow Bears reporter Gene Chamberlain on Twitter @CBSBears.