Best and worst QBs against the blitz
Peter Keating
26 de October de 2011, 5:17 PM
t Facebook t Twitter

Let's be honest: Tim Tebow didn't lead the Broncos to their comeback victory on Sunday. He wasn't even on the field for the two biggest plays of the game: D.J. Williams' sack-strip-and-recovery at the Miami 36-yard line with 9:53 left in overtime (win probability added: plus-52 percentage points, according to ESPN Stats & Information) and Matt Prater's 52-yard FG four plays later (WPA: plus-44 percentage points). But it still makes as little sense to trash Tebow as it does to worship him: we just have to keep watching him play, until we see which triumphs, his alleged knack for winning or his supposedly objectively subpar quarterbacking skills.
Here's what we do know, however: After flailing against extra pressure just about all day, Tebow started blowing away Miami's blitz late in the fourth quarter and the Dolphins failed to adjust, which is what allowed the Broncos to pull into a last-gasp tie. Through the first 57 minutes, when Miami sent five or more pass-rushers, Tebow didn't complete a pass, scrambled just once for 5 yards and took four sacks. Against extra pressure in the final 10:31, however, he was 3-of-5 for two touchdowns, a first down and just one sack. Yet the Fins kept coming; they blitzed almost as often during that stretch as they had the entire rest of the game.
The Dolphins, you see, were blitzing the way most teams blitz: by feel. Defenses tend to add pressure when the situation seems to call for turning their intensity up a notch, and the more desperate the scenario, the more aggressive coaches get. But Total Quarterback Rating reveals that teams aren't blitzing anywhere near as effectively as they could be. In particular, it shows that defenses aren't paying enough attention to whom they're blitzing, as opposed to when.
This season, NFL starters have an average QBR of 60.2 when facing four or fewer rushers, and just 48.4 when facing five or more. But there's a lot of variation in how individual quarterbacks respond to blitzes. And check this out: the correlation between change in QBR when facing extra pressure and how often QBs face additional rushers is just 0.1. In other words, there is almost no relationship at all between how much worse (or better) a guy does when he gets blitzed and how frequently defenses actually blitz him.
Among quarterbacks who have started in 2011, here are the 10 worst against the blitz by QBR:

And here are the 10 best:

So now we see what Rex Grossman's problem really was: opponents didn't blitz him enough! Seriously, even though extra pressure is far more effective against the first list of QBs, opponents are blitzing them on an average of just 32 percent of plays, while blitzing the second group of QBs, who actually improve under added pressure, on an average of 31.1 percent of plays. Sam Bradford is getting blitzed more often than any quarterback in the NFL (43.9 percent of attempts), which makes sense, because his QBR drops by 15.3 points when he faces extra rushers. But, although Matthew Stafford's QBR plunges even farther (18 points), he's getting blitzed less frequently than any other QB (17.8 percent of attempts).
Many teams probably deploy the blitz indiscriminately because they don't have the statistical tools to figure out whether it's worth it to start sending, or keep adding, extra pass-rushers while cutting back the number of men in coverage. This season, NFL starting QBs are taking more sacks when they're blitzed than when they face four or fewer pass-rushers (7.5 percent of drop-backs vs. 5.4 percent) and losing more yards per sack (6.8 vs. 6.3). But they're also throwing for more yards per attempt (7.4 vs. 7.3) and fewer interceptions (2.5 percent of attempts vs. 2.9 percent) when facing extra rushers. How should a team evaluate this mishmash of tradeoffs? Not to keep beating a dead horse, but passer rating is no help, because it doesn't include sacks at all. Indeed, starting QBs have just about the same average passer rating when facing five or more rushers (85.1) as when they face four or fewer (85.6). It's necessary to look at all results (not just passing attempts) by down, distance and leverage -- the kind of play-by-play analysis QBR provides -- to see the effects blitzing has on various QBs.

Four QB tiers against the blitz
Digging a little deeper with QBR, we find that quarterbacks fall into four distinct families in how they respond to the blitz. First, there are QBs whose performance declines when facing five or more rushers, and falls even further when facing a rush from at least one defensive back. This is the conventional-wisdom response to pressure -- the more you're hit with, the worse you do. But of the 34 QBs who have started in the NFL this season, only 13, or about 40 percent, fall into this category of "Normal Humans." This group includes several of the league's new or untested faces, such as Andy Dalton, Colt McCoy and Curtis Painter, but also Drew Brees, Mark Sanchez and Michael Vick.
Second, a group of nine QBs are better under pressure than against a four-man rush. We can call these guys "Men of Steel with Great Receivers." Six are actually the direct opposite of the Normal Humans: they're not only better facing five or more rushers, their performance improves even more against secondary blitzes. This group includes Aaron Rodgers, Ryan Fitzpatrick, Josh Freeman, Philip Rivers and Matt Ryan -- and, oddly enough, Alex Smith. The more aggressively you go after these QBs, the more you hurt your own team.
Third, there's another group of nine QBs who are affected by extra pass-rushing linemen and linebackers, but not bothered so much by secondary blitzes. This group includes Jason Campbell, Tarvaris Jackson, Cam Newton, Donovan McNabb and Ben Roethlisberger. Notice a pattern there? We'll call them the "Mobile Play Busters." Big Ben is an extreme case here: his QBR actually goes up when he faces a secondary blitz, even though it goes down when he faces extra pass-rushers out of other formations. The basic message against all these guys is: blitz them if you like, but keep your defensive backs at home.
Finally, there's a group of three QBs whose QBR improves against five or more regular pass-rushers, but drops when facing a rush by one or more defensive backs: Tom Brady, Eli Manning and Matt Schaub. This is a recognizable family, too: guys who are so used to the luxury of big, stable, effective offensive lines that they routinely find open receivers against traditional blitzes, but who can get rattled when a DB streaks into the backfield. Against these "Don't Disturb My Side of Beef" quarterbacks, the lesson is the opposite of that for facing the Mobile Play Busters: If you blitz them at all, send secondary pressure.
So now you know: knowing your opponent should be a critical factor in choosing whether and how to blitz. And maybe by the end of the season, we'll figure out which of these categories Tebow belongs...
Next >

t Facebook t Twitter
MÁS COBERTURA NFL
PORTADA NFL
RESULTADOS Y CALENDARIOS
NOTICIAS
EQUIPOS
JUGADORES
POSICIONES
ESTADÍSTICAS DE EQUIPO
ESTADÍSTICAS INDIVIDUALES
Regresar Arriba
Portada ESPN Deportes
In English
Ayuda y Comentarios
Buscar
Condiciones para el uso
Anuncios basados en intereses
Política de Confidencialidad/Sus Derechos de Confidencialidad de California
INGRESAR