The good news for Chicago is that Green Bay's defense has been almost as bad this season, and will be without Clay Matthews (broken thumb). Green Bay ranks 30th in DVOA against the opposition's No. 1 receiver; I don't know if that means Brandon Marshall or Alshon Jeffery, but someone is going to be open. Marshall and Jeffery will be particularly strong weapons in the red zone, where Chicago's offense ranks ninth on red zone passes and the Green Bay defense is 30th.
Before they get down near the goal line, the place for Chicago to look for big gains is going to be on second down. The Bears' offense ranks fifth on second-down plays, while the Packers' defense is 30th, including a dead-last ranking against the run.
Things are very different now. The Eagles have been red hot over the second half of the season, while Dallas has been in decline. Since Week 10, Philadelphia has the best offense in the league, according to DVOA ratings, and Dallas has the worst defense.
The Cowboys may not be able to slow the Philadelphia attack, but the Eagles will slow themselves if they don't recognize the strengths of the Dallas defense on film and devise their game plan accordingly. The Cowboys are very strong in a couple of specific ways that counter common Philadelphia strategies. For example, screens are a big part of the Eagles' passing game, but the Cowboys have allowed the lowest QBR in the league against screens (7.7). And the Cowboys have allowed just 3.24 yards per carry on read-options, fourth best in the NFL.
Much of the Cowboys' strength against these plays has to do with Sean Lee, who won't be playing this week. But why even take the risk that the Cowboys are good against such plays when it will be open season when Foles sets up with more conventional passes? Brandon Carr and Morris Claiborne have each given up more than 9.0 yards per pass, according to our game-charting data. The Cowboys also rank just 30th in DVOA against tight ends, so Brent Celek and Zach Ertz should play much bigger roles than they did in the first game.
It's hard to know what to expect on the other side of the ball with Kyle Orton likely replacing Tony Romo. But we do know that the Eagles' defense has improved from 30th in DVOA from Weeks 1 through 9 to 13th from Weeks 10 to 16. Philly's D should also be able to keep DeMarco Murray from making big highlight runs; the Eagles are the best defense in the league when it comes to preventing open-field yards, or yards that come more than 10 yards past the line of scrimmage on a rushing play.