LAKE FOREST, Ill. -- For the third time in three road games, the Chicago Bears' defense could face a third-string quarterback if Joe Webb starts for the Minnesota Vikings on Monday night.
The possibility of facing Webb, who has made just five NFL pass attempts, could be considered another stroke of good luck in a season full of similar breaks for the Bears, but really good fortune would be facing the Vikings without running back Adrian Peterson.
Peterson missed practice time this week because of ankle and knee soreness. Coming off their worst effort of the season, the Bears' defense is still gearing up to defend against a player who has been a nemesis over the years.
"He's a great running back," linebacker Brian Urlacher said. "I know he's a little banged up right now, but I'm sure he'll be ready to go on Monday night."
Peterson's first huge game as a pro came against the Bears with a three-touchdown, 224-yard, 20-carry effort in his rookie season of 2007.
During Peterson's first four games against the Bears, he averaged 6.2 yards per carry and eight touchdowns. However, in the past three games, he has been held to 3.5 yards per carry and three touchdowns. And in Chicago earlier this season, Peterson gained his lowest total against the Bears, 51 yards on 17 carries.
The Bears insist nothing has changed in their approach. They're just doing it better.
"Just getting in our gaps, just tackling, guys swarming around him," linebacker Lance Briggs said. "He is not always a guarantee if you're one-on-one with him, that you're going to bring him down. As long as we've got 11 guys flying to the ball, we give ourselves a chance to get him down."
Cornerback Tim Jennings called it a nightmare for a defensive player to find himself in the open field, one-on-one against Peterson.
"One thing about this defense, guys are running," Jennings said. "So you're never going to be by yourself tackling that guy. You've just got to play your leverage, force him back into the defense where your help is at. I think you just have to minimize his game. He's going to get his carries, he's going to get his yards."
Last season, the Bears forced a key Peterson fumble in overtime at home and won, and they also got him to fumble in a loss at the Metrodome. Peterson's fumbling problems received more attention after similar problems in the playoffs, but this season, he hasn't lost a fumble.
"Obviously he's very conscious of it, you can tell that," Bears defensive coordinator Rod Marinelli said. "It's not been popped up, so it's a credit to him. He's cleaned that up. Part of our deal is we've got to go take it away."
Easier said than done for the Bears' defense in recent games. Chicago has forced just two turnovers in four games and hasn't caused one in two weeks.
"We have to take the ball away," coach Lovie Smith said. "That's how we play football. For whatever reason, we haven't been able to do it. Last week, we had opportunities. We dropped interceptions, but I saw guys attempting to strip the football. They'll eventually come. Hopefully it will be Monday night."
In Webb, the Bears see a player similar in style to Michael Vick. They beat Vick and the Philadelphia Eagles 31-26 earlier this season.
"This guy can move now," Marinelli said of Webb. "He is fast. He sees a crease and he'll take off. So we've got to make sure we're disciplined in our rush lanes, that we overlap; all the things that we have to accomplish."
The 36-7 loss to the New England Patriots last Sunday still stings defensive players.
"It's a very prideful bunch of men now," Marinelli said. "That's a strong-willed group, with great pride in what they do, and that's why they're good and that's why we'll continue to be good."
Copyright 2010 by The Associated Press