Last season, the Chicago Bears' defense was No. 4 in points allowed, but this year it is No. 20 through Week 4. A year ago, the Bears were No. 2 in rushing yards allowed; this year they are No. 31.
"That's a complete 180," safety Chris Harris said. "Everybody's taking a step back and looking at themselves in the mirror. We don't point any fingers around here. We just have to get better individually (and) as a group."
The personnel is essentially the same, although Harris missed the previous three games with a hamstring injury. So what's wrong with the Bears' defense?
CB Tim Jennings
"I just think we've had some breakdowns fundamental-wise, overshooting some tackles," defensive coordinator Rod Marinelli said. "For us to get back on track, that has to (improve). They know it, and we know it."
Opponents had scored at least 27 points against the Bears in three straight games entering their Monday night game. The Bears permitted that many points just twice all last season, and not at all in the first 12 games.
Every 2011 opponent had at least 382 yards; that happened just four times in 2010.
"We've given up a lot of points and yards, which isn't a good thing," linebacker Brian Urlacher said. "Luckily we've managed to win two of those games. We're just not making big plays. We're giving up too many long runs; too many long passes. We're giving up big plays and not making any ourselves. We have to figure out how to get back to the way we used to play."
The Bears really have missed the big play. They've intercepted just three passes, and Urlacher has two. No one who has started a game in the secondary this season has a single interception. Nickel corner D.J. Moore's pick in Week 4 is the only one by a defensive back.
Lance Briggs leads the Bears with 46 tackles, but just two have been for negative yardage, and the Bears have just nine tackles for loss as a team. Last year they had 49. And the Bears are 25th in the league with just eight sacks.
The defense has already allowed 17 pass plays of 20 yards or more, on pace for a total of 68. Last season it allowed just 44. Run defense is almost as bad, big-play wise. In 2010, opponents had 45 runs of 10 yards or more. But the Bears had already allowed 14 this year after four games, on pace for 56.
The Bears' defense was No. 24 in rushing yards and No. 28 in average gain per rush allowed through the first four weeks, an ominous stat heading into the Week 6 game against the Vikings, who were No. 3 in rushing yards and No. 1 in average gain per run.
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