Are The Chiefs Blitzing Their Linebackers Less In 2011?


Yesterday we dove into fun with statistics to try to figure out which Kansas City Chiefs were rushing the passer and how efficient they were in doing so.

We figured out that Kansas City’s defensive line was far below average at pressuring the QB when compared to other 3-4 defensive fronts.

Later in the day, AA staffer Lyle suggested that one of the reasons Kansas City is struggling to pressure the QB, is because the injury to Eric Berry has limited what the Chiefs can do defensively. He pointed out that the Chiefs are especially limited in how much they can blitz their linebackers. He correctly pointed out that in most 3-4 defenses, a majority of the team’s sacks come from their linebackers.

Lyle wasn’t making an excuse for KC’s pass rushing futility along the defensive line. It is clear that Berry or no Berry, the defensive line’s performance is below average in the pass rush department. However Lyle was suggesting that Berry being out means the Chiefs are dropping defenders into coverage more and thus blitzing their linebackers less. The lack of linebacker blitzing, Lyle suggested, not only hurt KC’s overall chances of pressuring the QB but also put more strain on the defensive line, thus making their job harder.

I thought it was an interesting point so I decided to dive into the numbers to see if it was true. Are the Chiefs blitzing their linebackers less than they would if Eric Berry was still playing? Are KC’s defensive lineman performing worse in the pass rushing department this season without Berry than they did last season?

Let’s look at the numbers and find out, after the jump.

The great think about all these discussions is that we can get a pretty good idea of what is really happening by simply looking at the reality of the numbers.

I went into the numbers and compared 2010, when the Chiefs had Berry, to 2011 when they do not.

In 2010, the Chiefs had 989 plays run against their defense that were either a run or a pass. The ratio was 581 pass plays to 408 runs. Remarkably, through 8 games in 2011, the Chiefs have had almost the exact same number of plays run against their defense. So far, it is 494 plays, 260 pass and 234 run. This is through eight games so if you double that, you see the Chiefs are on pace to have 988 plays, run or pass, run against them in 2011, one play less than in 2010. So these snaps counts are almost identical.

The 2010 Chiefs were thrown on 581 times and sent linebackers after the passer 1057 times.

Thus the Chiefs sent an average of about 1.8 linebackers after the QB per pass attempt in 2010.

In 2011, through eight games, the Chiefs were thrown at 260 and sent linebackers after the passer 454 times.

Thus the Chiefs have sent an average of about 1.7 linebackers after the QB per pass attempt in 2011.

Base on these numbers, Lyle is correct that the Chiefs are sending few linebackers after the QB on passing place at about an average pace of 1 linebacker rush per ten pass attempts. Teams are throwing against the Chiefs about 33 times per game, so that means about 3.3 fewer linebacker rushes per game in 2011, which equals out to 52 fewer linebacker rushes over the course of a 16-game schedule.

When we look at production, however, the gap is much larger. The 2010 Chiefs got 40 sacks, 51 QB hits and 182 QB pressures.

The 2011 Chiefs are on pace for 18 sacks, 38 QB hits and 86 pressures. So the Chiefs are looking at a 55% drop in sacks, a 25% drop in QB hits and a 53% drop in pressures.

While these numbers give us a better indication of what is going on, it is still impossible to prove or disprove Lyle’s argument. Even if the Chiefs were to send linebackers at the same rate as they did in 2010, which would be 52 more linebacker pass rushes over the course of the season, how are we to quantity what effect that would have on the rest of the pass rushers, particularly the  guys on the defensive line? Would 3.3 more linebacker rushes per game increase Glenn Dorsey’s number pressures? By how much? What about the change of personnel? How do we measure the impact of new faces like Kelly Gregg, Allen Bailey, Justin Houston and Cameron Sheffield vs. the loss of Mike Vrabel, Shaun Smith and Eric Berry?

All of these things cause a chain reaction that greatly impacts the defenses ability to get after the QB compared to last year’s group.

What the numbers can tell us, however, is how the team is performing in their goal of rushing the passer this year. They can tell us which players can consistently get pressure on the QB when given the opportunity this year, in this system, in this set of circumstances.

The results tell us that for the most part, the Chiefs are failing miserably. It doesn’t really matter if Eric Berry is on the field or not. Unless the goal of this year’s Chiefs defense with this crop of players is to not put pressure on the QB, the scheme and the players are failing.

And if the Chiefs don’t figure out a solution, whether it be with the scheme or with the players, teams will continue to challenge them through the air.