Big test for Bears defense

Posted by ESPN.com’s Kevin Seifert

In case you hadn’t heard, Chicago is playing in the NFL’s marquee matchup Sunday night. The Bears’ matchup with Atlanta will feature a pair of one-loss teams who played one of the most dramatic regular-season games of 2008.

The Falcons have lost only one home game during the Mike Smith/Matt Ryan era, going 9-1 over that span. As Larry Mayer of ChicagoBears.com points out, that one loss came to Jay Cutler and the Denver Broncos last season.

For me, however, the most interesting aspect of this matchup will be its role as a measuring stick for the Bears' defense. Two key points here:

The whole point of overhauling the defensive coaching staff was to improve against the pass, and Atlanta’s Ryan has the NFL’s sixth-highest passer rating (102.9) this season. Ryan pretty much had his way with the Bears in the teams’ 2008 matchup, completing 22 of 30 passes for 301 yards and a touchdown. If the Bears’ offseason changes don’t translate into a better performance against the likes of Ryan, then its hard to imagine they will have a big impact as the season unfolds.

You’ll remember that last season, their rush defense was excellent. The Bears ranked fifth in the NFL with an average of 93.5 yards allowed per game. They also held Atlanta to 75 yards on 30 carries; the Falcons finished the season averaging more than double that total per game.

This season, the Bears are giving up -- yes -- 93.5 yards rushing per game. They also rank fourth in the NFL with 31 negative plays, as you’ll see in the accompanying chart. What I’m building to: If they once again stifle the Falcons’ running game, we can pretty reliably conclude that they’ve maintained their strong run defense.

I’ll have more on Thursday relative to Cutler’s performance against the Falcons last season, as well as some interesting numbers he has produced in his first four games with the Bears. Until then….