Air and Space: Bears and Lions response

The Bears' secondary managed to keep the Lions in check on long third downs last Sunday. Jerry Lai/US Presswire

We're continuing our weekly look this season at the Air and Space facet of this division, but as promised last week, I'm planning to introduce a second level of pass-happy analysis. How each NFC North team reacts to that shift in offensive focus will be a fascinating, and probably crucial, element to the 2010 season.

So let's jump into that angle right away here in Week 2, using two parameters we set out this spring. Since the Chicago Bears and Detroit Lions played our only divisional game last weekend, let's look at how the Bears' defense performed on third-and-long -- one of their 2009 pitfalls -- and how the Lions defense stood up against downfield passes. First up is the Bears.

As you remember last spring, we put forth a theory that suggested the Bears left themselves vulnerable to third-down conversions last season because of over-blitzing. The idea was that too much blitzing left mid-range receivers open too often, providing too-easy third-down opportunities for offenses. Indeed, Bears opponents had the NFL's best passer rating on third-and-8 or longer last season, completing 67.6 percent of those passes and averaging eight yards per attempt.

The Bears brought down those numbers significantly Sunday at Soldier Field. According to ESPN's Stats & Information, the Bears brought an extra pass rusher on 30 percent of their defensive snaps -- down from an average of nearly 43 percent per game last season. As the first chart shows you, what was supposed to be an explosive Lions offense averaged 3.9 yards per attempt on eight passes when facing third-and-8 or longer. They completed five of those passes but converted only one of them for a first down.

The easy explanation is that the addition of defensive end Julius Peppers gave the Bears more confidence in their base pass rush, necessitating fewer blitzes and more defenders devoted to coverage. We'll see if that was a one-game decision or if it becomes a trend for the Bears this season.

Now let's move on to the Lions. As we discussed in the spring, the Lions' pass defense was horrendous on pretty much all levels last season. Particularly galling was their performance against the longest of downfield passes -- those that traveled at least 21 yards in the air. Opponents completed more than half of those throws last season, averaging more than 41 yards per completion.

This spring, we suggested that an improved pass rush could reduce the time required for those passes. On Sunday, it did. The Lions sacked quarterback Jay Cutler four times, and as the second chart shows, only 60 of Cutler's 375 passing yards came on those kinds of downfield throws. (One was the game-winning touchdown, a 28-yard pass to tailback Matt Forte.)

But as it turned out, stopping the downfield pass wasn't enough for the Lions. Cutler, in fact, burned their defense on short-range passes. As the third chart shows, Cutler had a 117.9 passer rating on 24 passes that traveled 10 yards or fewer past the line of scrimmage.

In general, you would rather have teams dinking and dunking than heaving the ball deep. But on Sunday, the Bears moved the ball throughout the game in that fashion and then won the game on a downfield pass.

To be clear, a one-game sample size leaves us nowhere close to drawing any conclusions. Consider this Act I of a 16-act play. (Or something like that.) We'll update these trends in this space periodically through the season, and when it's over we'll see if either team made consistent progress and whether it mattered to the bottom line.