by Sterling Xie
Quarterback evaluation tends to receive more scrutiny than the Zapruder film. And while the position's magic bullet formula may never reveal itself, one universally accepted maxim is that a quarterback must be able to handle pressure. In conjunction with ESPN Stats & Info, the Football Outsiders game charting project annually tracks pass pressure results. Starting with offensive pressure numbers, we'll take a look at these charting results, which will be available in Football Outsiders Almanac 2015 next month.
Penned by Scott Kacsmar, last year's rendition of this article found a lot of inconsistencies in how quarterbacks perform under pressure from year to year. Part of this stems from sample size, since we're only dealing with a quarter of each passer's plays, and the general havoc of a typical pressure play lends itself to wider variation over time. Even the amount of pressure a quarterback sees doesn't tend to affect how he performs with pass rushers in his face. For 2014, the correlation between pressure DVOA and pressure rate was -0.16, suggesting only a tiny negative relationship between the two stats.
A couple commenters last year wondered about pressure in conjunction with blitz rates. At first glance, it appears that blitzing is generally more effective than normal plays. In 2014, defenses generated pressure on 33.9 percent of all blitzes (defined here as any play with five or more pass rushers), while schemes with four or fewer rushers generated pressure only 20.4 percent of the time. The DVOA gap between blitzes and non-blitzes, though, was much closer. This is mostly because defenses that can generate pressure with a four-man rush benefit from the extra defenders left to play pass coverage. The following table shows how offenses fared vs. blitzes and non-blitzes in 2014:
|2014 Offensive DVOA vs. Pressures and Blitzes|
|Play||Overall DVOA||Pressure Rate||DVOA, Pressure||DVOA, No Pressure|