This time, they might need to be equally concerned with Jared Allen and his fellow defensive linemen.
The disruptive Vikings will try to take advantage of a beleaguered Bears offensive line and claim consecutive victories for only the second time in two seasons Sunday night.
Peterson had a season-best 122 yards and matched a career high with three touchdowns last week as Minnesota claimed its first win of the season, routing visiting Arizona 34-10. The Vikings (1-4) got two sacks apiece from Allen - giving him an NFL-best 8 1/2 - and fellow defensive end Brian Robison, who is tied for ninth in the league with 4 1/2.
Allen has 8 1/2 sacks in six career matchups with Chicago and had two in the previous game at Soldier Field, a 27-13 loss Nov. 14.
"(The Vikings) are going to let that front four go to work, and we have to find a way to block them," said Bears quarterback Jay Cutler, who has thrown for 13 TDs in his five games against the Vikings.
Minnesota is tied for second in the league with 16 sacks and its defensive linemen have collected all but one of those. The Vikings will try to use that pass rush to claim only their second win in 11 games in Chicago and first since 2007.
The Bears have allowed the third-most sacks in the league (18), and Cutler was taken down three times - and hurried countless others - during a 24-13 loss in Detroit on Monday night.
Chicago's offensive line also committed a stunning nine false-start penalties.
"I'm sure they're going to do everything possible to fix some of the problems they had on Monday night and during the season. We got to be prepared to adjust to any changes they make," said Vikings coach and former Bears cornerback Leslie Frazier. "We need our pass rush to be working for us."
While scrambling often, Cutler managed to throw for 249 yards and a touchdown against the Lions, and Matt Forte topped 100 yards for the second straight game with 116 on 22 carries. Chicago (2-3), though, only scored three points after halftime and gave up its second touchdown of 70-plus yards in the third quarter.
"It's time to do some soul searching and see what each of us is really made of," cornerback Charles Tillman said. "We can either tuck our tails between our legs and go run away or man up and fight and get this thing turned around."
The Bears gave up a season-worst 181 rushing yards in the loss and are surrendering an NFL-worst 5.7 yards per carry, but they've held Peterson to less than 100 in each of the past two games in Chicago.
He gained 51 yards on 17 carries at Soldier Field last November and failed to score for the first time in seven matchups.
Peterson was nursing ankle and knee injuries during a 40-14 loss to the Bears on Dec. 20.
To snap their three-game skid against the Bears, the Vikings could use a similar performance from their running back and a better one from Donovan McNabb. The veteran quarterback's completion percentage (56.8) and yards per attempt (6.43) both rank 27th in the league.
McNabb hasn't thrown for more than 262 yards in any of his seven regular-season matchups with his hometown team, but has prevailed in five of those, including a 17-14 victory with Washington last season at Soldier Field.
He might have former Bears receiver Bernard Berrian back to help him. Berrian was on the inactive list for last week's game for undisclosed reasons, a punishment he says he's "already over."
"I don't foresee any future problems. I really expect him to play at a high level for us and play well," Frazier said.
Berrian, who has two catches for 37 yards, was part of a brief Twitter feud with a state lawmaker following a 22-17 loss in Kansas City on Oct. 2. Another former Chicago wideout, Devin Aromashodu, has 115 yards and a touchdown over the last two games.
The Bears, meanwhile, are unlikely to have Julius Peppers available. The defensive end, who signed a six-year deal worth $91.5 million before the start of last season, was listed as doubtful after missing practice Friday due to a sprained left knee. He had returned late in Monday's game after suffering the injury.
Chicago expect to see defensive end Corey Wootton return, though on a limited basis. After missing three games with a knee injury before returning Oct. 2, he sat out the loss to Detroit with a broken hand.
The Bears are tied for 21st with nine sacks, five of which came in a season-opening win over Atlanta.
A fourth straight victory over Minnesota would give Chicago its longest streak since a series-best six-game run Dec. 11, 1983-Oct. 5, 1986.
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