Audibles: NFC North Week 7 preview

Posted by ESPN.com's Kevin Seifert

Minnesota Vikings (3-3) at Chicago Bears (3-3), 1 p.m. ET

It's not often that the Vikings' passing game is involved in a key matchup of any game. But it will be interesting to watch how the Bears will approach Gus Frerotte and friends Sunday. The injury issues in Chicago's secondary have been well documented, and the Bears remember all too well how Minnesota tailback Adrian Peterson roughed them up for 224 yards last year at Soldier Field.

As a result, the Bears will have to take a risk somewhere. Do they load up against Peterson and hope their remaining defensive backs can stick with Bernard Berrian and Bobby Wade? Or will the injuries and Frerotte's recent success -- he is averaging 261 yards per game over the past three weeks -- force the Bears to pull their additional run support away from Peterson?

Our guess is Chicago coach Lovie Smith will do everything necessary to prevent Peterson from showing up his team for a second consecutive year. In that scenario, it will be up to Berrian and Wade -- who have combined for 23 receptions and 376 yards in the past two weeks -- to take advantage. The Bears would most likely be counting on Corey Graham and Nate Vasher to stop them.

Detroit Lions (0-5) at Houston Texans (1-4) 4:05 p.m. ET

More than ever, expect the Lions to run, run, run and then run some more. The trade of receiver Roy Williams extracted some of the juice from an already punchless offense, and it's hard to imagine Detroit calling on new quarterback Dan Orlovsky to air it out.

Coach Rod Marinelli will use the rest of this season to hammer home the philosophy he hopes to carry into 2009, assuming he gets the chance to coach that team. Marinelli wants to see his defense swarming and his running game chewing up the clock; the Lions achieved half of that goal in their 12-10 loss last Sunday at Minnesota.

Marinelli will also have to work to keep his players interested. After a tumultuous week in which the team traded Williams and put quarterback Jon Kitna to pasture, it wouldn't be beyond many players to consider the season over. Sure, they're fighting for jobs. But malaise can take over even the most proud of players.

Green Bay Packers (3-3) vs. Indianapolis Colts (3-2), 4:15 p.m. ET

The Packers, much like the Bears, are hoping their depleted secondary can hang on for one more week. Green Bay is one game away from its bye, but that won't mean much when Indianapolis arrives Sunday at Lambeau Field.

Cornerback Al Harris (spleen) and safety Atari Bigby (hamstring) returned to practice this week, but the Packers won't have Harris and aren't sure about Bigby for Sunday. It could be one more week of Aaron Rouse at safety and Tramon Williams at cornerback.

Williams has played well, but the Packers are best with Harris at corner and Williams in the nickel. The Colts are vulnerable but only if Green Bay can limit their big plays in the passing game.