First I'll post the main a graphic, then you can wade though the article if you like. It will be discussed below.
How I Came to Study the Jets Pass Rush
I've been fascinated by the changing face of the Rex Ryan Jet defense. One of the reasons is that though I might consider myself an astute watcher of the game when I started looking into the numbers this year - numbers of how often he sent a blitzer, or how effective pass rushers were...and then into the recent history of the Jets I was pretty taken aback how radically the defense has changed since it's initial heyday in 2009. I wrote a post about that called The Rise and Fall of the Rex Ryan Blitz which in season examined the growing trend of conservativism in Rex Ryan defenses, despite the robust reputation of the opposite. You can still hear Dan Dierdorf saying in 3rd and long "This is where no Offensive Coodinator wants to be!" You can read that article, but this graphic showing the percent of times DBs were sent is probably the best crystallization (the 2013 data is incomplete in this graphic).
How Many Men Sent?
What really first alerted me to this was that I was playing around with ProfootballFocus.com's data and figured that if you had all the pass rush attempt totals you could just divide by total pass attempts and get a pretty good data measure on which teams are sending a lot of defenders, on average, and which weren't. But when I ran the numbers, mid-season, I was shocked to find that the Jets were pretty low in average defenders sent. So much did my Rex Ryan bias take hold of me that I just assumed that the PFF data must be wrong, and I even wrote and asked them about it. They of course said their data was just fine. So I knew I had to wait for the year to end to build a significant picture. This is how the Jets stacked up, on average:
Only six NFL teams sent fewer men per pass attempt than the Jets. We are a long way from home. Instead of the blitz-happy Rex Ryan, Captain Chaos, we have one of the most conservative defensive coaches in the league, in terms of rushing the passer. It is okay if we want to applaud the Rex Ryan approach, but we do need to keep our eye on just what it is he is choosing to do.
Now I never seen this kind of data before, so it may have pitfalls. I present it preliminarily. I simply divided total pass rushes counted by profootballfocus.com by the total passes defended as counted by profootballreference.com. Also, like a run stat like yards per carry there would be game situations which would affect this average. If a team is up big in the 4th they aren't going to be rushing the passer with many men, just as they may run the ball to a low average burning the clock. And the opposite may be the case for a team behind. Ideally 4th quarter stats in two or three score advantages could be thrown out. Another factor may be that if a defense is porous and does to present many pass rush friendly downs, or the opposite, this too may affect the average. Just the same, it is a nice little piece of data, and it does give us ball park. The one team that really leaps out is SF which has an unusually low number of rushers sent. I checked the numbers several times and they seem correct. Maybe someone who knows the 49ners well can comment, but he only thing I can guess is that not only did their few blowout wins contribute, but also that they simply can get pressure on QBs with only 4 (or possibly fewer) rushers. The SF number does give me pause about this stat though. If I had the time I'd check across other NFL seasons.
The PRP stat - How Efficient
Now the SF case certainly points to an obvious truth. It isn't only how many you rush, it's how efficient you are when rushing. If you leave more of your defensive resources back in coverage and are still able to get pressure all the better for you. This brings us to the 2nd half of the equation. How effective were the Jets when they rushed? To me this goes to two levels of questions. How effective is the play call? How skilled or dynamic is the pass rusher (or host of pass rushers)?
Unfortunately the Jets not only rushed the passer infrequently, they were not very efficient when doing so. These are the league team numbers:
Only 7 teams were less effective rushing the passer than the Jets this year.
The Pass Rush Productivity (PRP) stat is a very simple one. It's simple, but it contains data many other stats simply don't. The formula is this: [(QB hits + QB hurries) x .75] + sacks / pass rushes. It operates as a kind of weighted percentage. When rushing the passer what is the chance of the rusher making an impact? I haven't seen PFF team PRPs, they give them by position, so I just calculated them by myself. What is nice about a team PRP is that it gives an excellent "scheme" picture. Because it is averaged across the roster, and all the play calls you can see just how effective or good the defense is at pressuring the QB. You can have a high PRP even if you don't rush the passer often (for instance by position corners and safeties do).
To give a little perspective on the PRP stat here are the average PRPs by position, using all pass rushes in the NFL:
And here is where the Jets averaged in PRP by position in relationship to the NFL average
There are only a few bright spots. Corners stand out with a 25 PRP, but this really has to be qualified because the Jets blitzed at corner only 12 times this year, and never with their primary corners (Cromartie, Milliner). The winner here was Trufant who had 2 hurries in his 5 blitzes. Not much to speak of. The one area of positive is the combined DE PRP of 6.4. It is a decent above average number, but in this defense pressure really doesn't come from the DEs. It has to come from elsewhere. You can see in the graphic above 3-4 DEs have the lowest PRP averages in the league. Where it really has to come from (if not the DBs) is the OLBers.
The Jets who performed at their position above league average in PRP were:
As much as everyone loved Snacks and his nickname is was a significant weakness when the QB dropped back. Ellis did not get a ton of playing time, but he was much better in pass rush. Douzable was also smartly used. But these were the stand out pass rushers in terms of efficiency, and they were right around average (or in non-impact positions). And as much as I loved Richardson, my favorite Jet, he just missed the cut off below average. Notably only 2 starters were (modestly) above average as a pass rusher at their position. - out of the 50% snap data Wilkerson tied for 12th (Corey Liuget, SD) out of 22 qualifying DEs, Davis was 13th out of 33 ILBers, Harris 14th.
The Full NFL Picture
Above we have the two variables graphed to show where the Jets were in relation to other pass rushing teams. On the bottom (x) axis is average number of men rushed per pass rush, on the left axis (y) is the team average in PRP. The red dot near middle is NFL average, and every team that finished in the top 10 in DVOA pass defense was turned yellow. There are probably a lot of team trends to be discovered in this data and I've love to know what others see. Personally I hoped for would be a relationship between the number of defenders rushed and PRP. There would, presumably, come a limit at which there would be diminishing pass rush returns. This I couldn't discover. On other notes looks like Denver had a very nice PRP, but a poor DVOA, so maybe coverage and call was the issue? The same with Detroit? In any case for Jet fans we found ourselves in the lower left quadrant among the least rushing, and least effective teams in the league.
What this means for Rex Ryan fans, I suggest, is that we are not really 1 year away. Pass Defense (aside from Pass Offense) is probably the most important dimension of a team and the Jets were very conservative and non-effective in pressuring the QB. If Rex Ryan has a master plan for the team, for instance building it from the DL on out, there is a way to go in terms of talent, on Defense, before he should be able to bring a Defensive power. And one of the most interesting things will be the tug of war of needs between the Offense and the Defense.
The Pettine Effect
Perhaps for Jet fans the most compelling team on the graph is the Buffalo Bills. The Bills took Rex Ryan's right hand man and made him Defensive Coordinator. And the Bills did pretty good in pass defense. They ended up with a Ryan-like number 2 in the league in DVOA pass defense efficiency (the Jets fell from 10th to 17th, and Buffalo was 22nd last year...the last time the Jets were number 2 was 2011). And they did it with a very high team PRP and sending a fair bit above average number of pass rushers. They ostensibly were where we would expect/hope the Jets would be. There were different rosters for both teams, to be sure, but with such stark differences in production, and rumors that it was Pettine who nursed Rex off the DB blitz juice the question will be begged: Was Pettine a more-than-significant part of brains behind Jet pass defense excellence?
Things in the Data
In my reading and stacking of numbers I crunched a few details out that may be interest to others, though I see no immediate significance.
The above is number of pass rushes out of the total pass rushes NFL pie, by position. Maybe those looking at NFL trends would like the pie chart.
The above shows the percent of total pressures that were a sack, hit or hurry by position. The only thing of note may be that 3-4 OLBers of all the defenders regularly on the line had the greatest chance of registering a sack rather than merely a hit. It stands to reason as they have the QB at the edge. It could be statistical quirk, but among PFF 50% Pace had the highest ratio of sacks to hits among such OLBers, and Coples had the 2nd worst. Perhaps this is the difference between knowing your position and not, or just being athletic enough to make that one extra move that makes the difference. Also interesting that ILB and CB blitzes were on the whole more efficient than safety blitzes at producing the sack.
As usual, these are hand-collected stats. There may be errors.