Minggu, 29 Juni 2008

Pass Protection, the Super Bowl, Tom Brady, and the Blind Side


Question: What is the second highest paid position in the NFL? (Quarterback is first.) Cornerback? Wide receiver? Don’t guys like Randy Moss and Terrell Owens make ridiculous money? What about linebackers? Wait, it must be running back: guys like Clinton Portis and LaDainian Tomlinson command huge salaries.

No.

Answer: The second highest paid position in the NFL is left offensive tackle. It’s not really even close. Since the highest paid position is QB, it stands to reason that you’d pay a lot to protect him. Interestingly, until free agency arrived, all offensive linemen were paid the same. Centers, tackles, and guards all earned similar salaries. And, as a whole, linemen fell somewhere in the middle of the NFL salary hierarchy. When free agency hit, the age of the highly paid left tackle arrived.

Why Left Tackle?

There is a two word answer to why left tackles are now paid so highly. The first word is “Lawrence” and the second word is “Taylor.” Under Bill Parcells and Bill Belichick, Lawrence Taylor destroyed opposing quarterbacks and helped the Giants win two Super Bowls. One legend tells of an opposing Quarterback calling a timeout because he couldn’t find number 56 before the snap. Identifying LT was typically necessary since the Giants moved him around on defense. But that time, the timeout was wasted: LT was simply catching a breather on the sideline. Whoops.


But LT’s hits did more than just derail a team’s passing attack for the afternoon. LT derailed careers. He knocked Joe Montana out for a season and, most famously, LT basically ended Joe Theisman’s playing career by inflicting some kind of multi-break spiral fracture of the likes not seen since the middle ages.

So the football reason that tackles are so highly paid – and the reason most practical to us here – is that an effective pass rush, particularly from a pass rusher that you cannot block, can totally shut you down. Such pass rush takes away large portions of your offense and forces you into predictable responses. The most sound of pass protections usually start out with the understanding that if the defense rushes five or six guys, you can pick them up, but your blockers will have to be able to block at least one defender one-on-one. No pass protection scheme can count on double teaming all possible rushers. If you can’t handle Lawrence Taylor man-for-man, then a five man rush becomes like a seven or eight man blitz, but also with sound coverage behind it.

I do just want to touch on the point about injuries and give credit for the above where it is due. Much of this discussion is the thesis of Michael Lewis’s book, The Blind Side.* Once modern passing teams became dependent on throwing the ball, the Quarterback, it became understood, became indispensable to team success. And once “pass rushing specialists” began to appear, one absolutely had to have guys who could block them. If your team can’t block them, it’s either going to be a long afternoon of sacks and incompletions, or your QB might end up in the hospital (taking your program or your team’s financial investment with him). Indeed, sport has no parallel for the quarterback who is consistently hit during his pass set-up and follow through. Imagine a freakishly large and fast linebacker like Shawn Merriman slamming full speed into a baseball pitcher in the middle of his wind-up, or Lawrence Taylor drilling Tiger Woods in the middle of his backswing. Remember, even LT’s 1990 New York Giants had to win the Super Bowl with their backup quarterback because their starter, Phil Simms, had gone down with an injury late in the year.

Blitzing: The All-Out Blitz

Contrary to what you might hear on TV, football is not really about “creating one-on-one matchups.” Sometimes this works, like if you’re a high school team and you have a future Randy Moss and they have a 5’10” guy who runs a 5.1 forty-yard dash at cornerback. Then one-on-one sounds great. But the better strategy is to force one defender into dealing with two offensive players. Think of option plays (one defender and two ball carriers), double-team blocks (two blockers and one defender), and good zone stretching pass concepts where one defender must account for two receivers (such as when a single free safety must deal with two receivers releasing free down the seams). An offense creates these two-for-one’s by forcing the defense to overcompensate somewhere else, such as where the defense is forced to commit two to cover one, or three to cover two receivers. One-for-one across the board will not get an offense home. Indeed, the Giants were always praying that they could get LT on a “one-on-one matchup.”

When most think of blitzing they think of all-out blitzes. It’s a truism that a defense may always bring one more guy than the offense can block: the ballcarrier’s counterpart. If an offense protects with ten the defense could still blitz eleven; if the offense protects with nine, releases one, and the QB stood back there the defense could still blitz ten. (See diagram.)



This has theoretical significance but is also (somewhat) practically irrelevant. The theoretical significance is that you can’t beat a defense by simply adding more blockers. But don’t make too much of this. On the one hand, you can’t solve blitzing problems by just adding more blockers because of the ball carrier’s counterpart problem evident in the diagram. But on the other hand, teams are less likely to blitz more people the more blockers you add. If you blocked with five most defenses might blitz six people 35% of the time; if you block with six they might blitz with seven 25%; if you protect with seven they might be willing to blitz eight 5-10% of the time; and if you protect with eight the likelihood of blitzing nine drops to almost nil.

Why that is, I’m not sure. Maybe it’s a matter for cognitive psychologists, in that there is an irrational risk aversion to creating the same scenario – a single extra rusher – that arises when the D must rush eight or nine that isn’t present when the defense only needs to rush six or seven to get that extra rusher. Some offensive guys think it is extremely irrational (and thus an exploitable irrationality) because an all-out blitz against a spread set gives their QB more places to go with the football, more receivers to criss-cross and rub, and more opportunities to get an open man. Other offensive guys play the perceived irrationality the other way, knowing that if they protect with seven or eight then they will deter blitzing.

Then again, maybe this behavior from defensive coaches is rational, because more blockers might create the same scenario – a free rusher – but that free rusher might have to come from farther away, thus giving the QB more time to find an open guy. I tend to think the picture is complicated, but there is much merit to this last contention. A 15-25 yard completion against a blitz is far more threatening (and thus a better deterrent) than a 5-8 yard completion which a spread set might require with only five or six blockers.

There are excellent passing teams that take a “protect-first” approach, where the idea is to hit big passes against all-out blitzes and to play the percentages that a defense will get deterred from blitzing, and there are spread-teams that rely on hot routes, multiple receivers and quick passes. These teams seek to invite the blitz, betting that if they can get athletes the ball in space then they will break for big gains. There are good teams that mix and blend the two approaches, and there are inefficient and weak passing teams that lack focus and discipline across this spectrum. Like much in football, it is only partially a matter of what you do and more significantly an issue of how well you do whatever it is you do.

But the upshot is that the all-out blitz is not really where the action is at, at least among evenly-matched teams in high school, college, or the pros. Dealing with the all-out man blitz is a threshold question: if you can’t beat it, your offense will be shut down; if your defense gets burned every time (and you keep going to it) you will have a long afternoon. In this way, the all-out blitz battle between offense and defense is an example of constraint theory playing out.

Basic Principles of Dropback Protection

This is a deep and varied subject, but we have to have a little background to understand how the pass rush/protection game plays out. There are two types of protection schemes: (1) area or zone schemes, and (2) man schemes. Some protections blend these two approaches, either explicitly or implicitly.

(1) Area Schemes: An area scheme is where a group of blockers set up in a given areas and then sort and pick-up whatever “trash” comes through. For example, if the center, guard, and tackle are responsible for one side of the protection, and the defense crosses and twists a couple defensive linemen and a linebacker. This is probably the soundest “protect-first” approach, and good teamwork will allow the line to deal with defensive creativity with a simple sound approach.

Problems with area schemes arise when you introduce runningbacks, tight ends, or H-backs into the equation. The problem is twofold:

(a) An area scheme could leave you with a terrible match-up, such as a runningback on a defensive end (or Lawrence Taylor).

(b) An area-assigned protector who is also a skill player (like a tight end, H-back, or runningback) has a difficult time releasing into the route if the defense does not blitz. So any of those skill players who you have assigned to an area scheme likely will not get out into the route, and you might only have three receivers trying to get open against seven pass defenders. For example, see the diagram below.

Above, we put the guard, tackle, and Y (TE) on an area scheme, making them responsible for the defensive tackle, the defensive end, and the Stronside linebacker (Sam or “S”). If they were to stunt or twist, we’d be in good shape, but look what happens here: the DT and the DE just rush, and the Sam linebacker drops into coverage. So now the Y has to stay in to protect (where he is matched up with a defensive end!), the tackle blocks no one at all, and, at most, we can only get four men into the route. There are ways around this, but I want to highlight the concern.

(2) Man Schemes: The offensive front will identify their counterparts on defense and block them where they go. This is not always absolute. Typically linemen will still employ a modified area scheme (where they will trade defenders who twist), but running backs and the like, because they are set back further away from the line, can go where their counterpart goes easier than a lineman can. Look at the diagram below, the RB is assigned to the Weak (“W”) linebacker on a “man” principle. Wherever he goes, he is responsible for blocking him. If Will does not rush, the RB will release into the pass route. Similarly, H is responsible for the Strongside linebacker (“S”), and if he does not rush, then H will release into the route.

Man blocking seeks to eliminate the problems we identified with area schemes: as in the diagram above, a “BOB” approach - short for “Big on Big” and “Back on Backer.” The idea is that the linemen will take the big defensive linemen (who also tend to rush the passer on most plays), while the runningbacks or H-Backs will block the linebackers, who are both more their size and less likely to rush the passer than a defensive lineman. So you avoid both area scheme problems: the matchups should be better for the offense and, if the defense only rushes three or four, your skill guys can still get out into the route.

(3) Combo protection: An extremely common protection is to area block one side of the line and man block the other side, typically the side with the runningback. There is some dissension among coaches, but my view is that almost all six-man protections employ this concept, whether they do it explicitly (as I advocate) or implicitly, as others do. The idea is that most teams find it advantageous to teach their linemen to area block stunts and twists, so you wind up with a combo concept. I first explained this protection years ago here. Note that this protection employs my preferred form of "area" or "zone" protection, which is the "slide" protection. The details are explained below, but each area-blocking lineman "slides" to the gap away from the callside. I advocate a "full-slide" for many quick game routes, but below is my half-slide, which is the most useful and versatile protection I know of.

The base rules for this protection are as follows: Linemen to the callside [here, the right side] block man on until the first bubble (i.e. uncovered linemen, though the term "bubble" helps prevent against confusion due defensive players stunting). [Here the first uncovered lineman is the center.] From the bubble to backside the other will linemen will all slide away from the callside to that gap, and, as we like to say, pick up trash. For example versus a standard four man front, with the center uncovered, the center, backside guard and tackle will slide that way. The playside guard and tackle will block man on. The RB blocks LBs inside to out, from the bubble to outside rusher, or if you like Mike to Sam. If they don't come he releases.


There’s another very important concept, the dual-read. The dual-read is simply where a blocker is responsible for two-men. Usually there is a one and two: if one comes, he gets blocked, if two comes, the blocker must wheel out and block them. If they both come, he will only block one and the quarterback and receivers must complete the pass before two can get to the QB. This is easy and common for runningbacks. In the 1980s and for much of the 90’s it was common to do this with linemen (such as guards), but the practice has significantly decreased because it’s hard for a guard to wheel out and block an outside rusher. It became much more difficult in the late 90s and 2000s because defenses became good at freezing the lineman so he couldn’t get out there.

The Pass Protection Chess Match

So after this romp across protection concepts, we’re ready to understand some basics about the chess match between offense and defense. But first, a few preliminary remarks.

More than any other factor, sacks are primarily a function of the QB holding onto the ball too long, protection be damned. Any coach worth his salt is going to hold a stopwatch any time his QB drops back in practice. TV announcers who seek out what lineman to blame often miss the point: the QB needs to get rid of the ball quickly. The QB has just a couple of seconds to release the ball. Only a small percentage of sacks in the NFL and college can fairly be laid at the linemen’s feet. Now, the QB may get pressured, or have to throw it away, but most sacks are the QB’s fault.

Further, it is up to the playcaller not to make the QB a sitting duck. No one should ever call four straight drop-back (or play-action dropback) passes in a row. If the defense is going to take target practice, you should at least make your quarterback a moving target. I mean, “that’s [your] quarterback.”

The two best changeups – other than the run game – are the three-step passing game (see also here) and the screen game. But remember: the three-step game, as Bill Walsh said, was designed to take away obvious opportunities from the defense, such as loose outside coverage. Three-step passes are not necessarily sufficient to sustain your offense, and further, good defenses will bait you into throwing quicks and then will come up to make the tackle. Similarly for screens, if a defense is prepared for it, it’s often a negative play. So it’s all about finding the proper mix. This is all consistent with constraint theory.

Finally, do not forget about half-rolls and sprintouts. The run-and-shoot was based entirely on the half-roll principle, and I explained the sprint-out sometime ago here.

The Zone Blitz, the Hot Read, and the Dual Read

Hot Reads

I think the “zone blitz” is maybe the favorite term of the uninformed football commentator (second only to that abominable word, “trickeration”). But what is a “zone-blitz”? A defense does not zone blitz every time a defensive lineman drops into pass coverage. In fact, the defense does not even have to drop a defensive lineman at all to zone blitz. (I set aside here the abstract theoretical question of what to call it if a defense has no defensive linemen on the field at all.)

Instead, as the name implies, a “zone-blitz” means exactly what it says: a defense “zone-blitzes” anytime it “blitzes” or rushes linebackers or secondary players and plays a zone – as opposed to a man – coverage behind it. That sounds simple, right? I suppose commentators try to fancy it up since it’s obvious that teams have played zone behind blitzes for as long as teams have thrown the football. But, nevertheless, for much of the last century, most “blitzes” were tied to man coverage.

The reason is that most zone blitzes left intolerable holes in the coverage. If the defense blitzed two guys from the same side, a receiver to that side would run a route to wherever those defenders had just left, catch a quick pass, and pick up nice yardage. So defenses would typically bring their blitzes with man coverage in an attempt to take away these quick passes, and the game largely became about personnel and a QB’s poise under fire. And the Run and Shoot, among other offenses, relied on their screen game to deter all-out blitzes, because if the defense blitzed and the RB carried out his fake block properly, there was no one to cover him and he romped for a big gain. As Homer Smith has explained:

[L]earn from the great Run-And-Shoot teams that did not get blitzed for 20 years. Block a known rusher with an inside receiver and keep a second defender at bay with a delayed pass threat. (The Run-And-shoot singleback would block the end-of-line rusher and break off of the block four times a game for screen passes. Not until the advent of the zone blitz was the vaunted offense blitzed.)

So why is talk and usage of the zone-blitz so ubiquitous now? The reason is that, especially if you do have athletic defensive linemen, you can play games with where you bring your blitzers from and solve the two historical problems. See the diagram below for the basic “Fire Zone,” the most common variety ofzone-blitz.

(1) You notice in the above diagram that the defense is “blitzing” the Middle (Mike, or “M”) and Strongside (Sam, or “S”) linebackers. Under the old way, before the modern zone-blitz became prevalent, a common strategy would be to try to hit a receiver from the spot where the defense just left. Either the TE on a quick pass or, as here, the outside receiver on a slant. But, the strong safety is able to rotate down and take that away. Why can he do that? Because the backside defensive end has drifted out to the flat, and allowing the coverage to rotate towards the side the blitzers have come from. This makes the QB’s reads very murky, and murky is bad when big defensive guys are about to crush you.

So it is not the mere fact that a defensive end has dropped out and this “confuses” the QB and he throws it to some big lineman, though that sometimes happens. Defensive coaches do not want to actually put their defensive linemen in the spot where they think the ball might go – they recognize that they are not good pass defenders. The hope instead is to “hide” that defender, but still use him to allow the rest of the guys to get in a basically sound zone. Here, if the QB throws the slant, the safety will pick it off and take it the other way.

The other thing you will notice, is that by blitzing the Mike and the Sam the RB – here “F” – must stay in and protect the QB. That is significant because somewhere else on the line, either the backside tackle or guard, or possibly the center based on the stunt, will wind up blocking no one. In coach-speak this is called “blocking air.” So the defense has gained an advantage in yet another way: despite only bringing five guys, which presumably the offense would like to handle with its five offensive linemen while releasing the five receivers, the offense is protecting with six and can only release four receivers into the route. This is the chess match.

As another point, I mention that zone blitzes - since they only rush four to six defenders - are really designed to destroy six-man protections, which have traditionally been extremely popular with pass first teams. Even two-back, one TE teams like Bill Walsh's 49ers typically used six-man protections. I touch on some of the other counters to the zone-blitz in this article, but the simplest, and most effective, is to simply use a 7-man protection scheme (one is diagrammed above under "Man Schemes"). Although it is more likely that you might lose a possible receiver to a protection responsibility, it is better that than to give your QB a difficult hot or sight adjustment read or that he gets sacked. Moving on.

(2) The second point is more basic, which is that the screen to the RB that Homer Smith referenced above, which against a man blitz required two defenders to watch, is now largely neutralized – or at least its effects mitigated – because like a normal defense you have linebackers and safeties reading the play who can come up to tackle the back if they read screen.

Dual Read

In 2004, the Pittsburgh Steelers made an impressive run through the NFL playoffs, beating the Indianapolis Colts (an offensive juggernaut) along the way, and polishing off the Seattle Seahawks in the Super Bowl. I’m sure the terrible-towel wavers found this significant for many reasons, but for me, it signaled another nail in the coffin of asking offensive linemen to dual read.

As shown above, it’s not uncommon to ask a running back or even an H-back to “dual read,” or read two different men to see whether they blitz. The QB knows that if only one or the other blitzes, then it should be taken care of. He only has to read “hot” – i.e. an expedited throw – if both blitz. In theory.

Now, many coaches still teach their linemen to dual read, but it is not easy to do. The Steelers repeatedly used this tactic to gain an unblocked or free rusher. Both the Seahawks and the Colts consistently used had their guards and center dual read, and the results were not good. Below is representative of what the Steelers would do:

The left guard, shaded in green, would be responsible for blocking either of the inside or outside linebackers to his side. In theory, if the inside linebacker dropped and the outsider backer blitzed, the guard would wheel out to block him. No doubt they practiced this all the time. What the Steelers did – and this was not revolutionary – was the inside linebacker would take a step or two up, thus “freezing” the guard, while the outside linebacker came flying towards the quarterback. The guard would try to recover, but too often he was late, and the play was destroyed.

Observe how powerful that is for the defense. They only rush four, maybe five defenders, and the other six or seven all drop into coverage. The secondary can watch the Quarterback’s eyes, and he is under incredible duress from an unblocked rusher. Indeed, if the defense can get an unblocked blitzer with only four rushing, they often would blitz someone the back was responsible for, figuring that the one-for-one trade in taking the RB out of the route was a good one. See, how one-on-one matchups does not win you the game, but instead this was an example of the defense winning a numbers game.

(As an interesting aside, in the Super Bowl against the Patriots the Giants cleverly inverted this concept: Linebacker Kavika Mitchell lined up over the center, while an outside rusher lined up in threatening position away from the side the running back was responsible for. At the snap, Mitchell head-faked as if he was dropping back into pass coverage, and the center – who no doubt had a dual read and was responsible for the outside rusher, and who knew he needed to move quick if he had a prayer of getting out there – cleared out. Mitchell, instead of dropping back, blitzed directly up the middle and sacked Tom Brady. Mitchell made a great fake, but the reason it was so open was because the center had protection responsibilities besides Mitchell. Again, dual reading by a down lineman is never easy. It is much easier for a running back who has more time to see the defense in front of him.)

The Sugar Bowl and the Super Bowl: Sometimes it’s Not About Xs and Os, It's About - Yes I Get It - Jimmies and Joes. Well Guess What? Joe sucks.

In both the Super Bowl and the Sugar Bowl, high-flying spread offenses (the Patriots were basically a spread team) were largely shut down because of an inability to protect the passer. And in both, there really wasn’t a lot of clever scheming going on, it was just lots of the Lawrence Taylor phenomenon: Who do you have that can block my guy? The answer for both the Patriots and the Hawaii Rainbows was, nobody. This was doubly surprising because both offensive lines had really performed quite well through the year: both units were disciplined, hard working, and did not blow assignments. Yet, they were exposed. The reality is that sometimes, good offensive line play is not enough. At the higher levels of football, if you’re going to deal with freaks of nature on defense, you need your own freaks of nature to block them. That’s why the best left tackles get paid so much, and why, as Michael Lewis’s book (link, amazon) chronicles, coaches at every level are searching for those kids who somehow combine behemoth size with incredible athleticism.

But there has to be something you can do, right? Football is about reacting to and neutralizing the other team’s strengths. The most striking thing about the Super Bowl and the Sugar Bowl was that neither team – the Pats nor Hawaii – ever seemed that interested in trying to add H-backs or extra running backs to “chip” protect on their way out. (I.e. while they release on a pass route they get a small block or “chip” on the good pass rushers to help the other linemen make their blocks.)

I will leave it to say that I was surprised that neither team did it more. But I think a partial answer is that what made those teams excellent was a complete commitment to a particular style, especially in Hawaii’s case where they were coached by the excellent June Jones. Their offense is based out of that four-wide set, and to suddenly put tight ends and other blockers on the field, well, then you’re not a Run and Shoot team. Nevertheless, the problem of exceptional pass rushers is not isolated, so there have to be a few other things to do. I can’t cover them all here, but he’s a few.

The first thing is you must use the defense’s aggressiveness against itself. The first thing to do against aggressive defenses is to trap them. Below is a diagram of the quick inside trap, and you can read about the famous “Draw Trap” here. The theory behind the trap is that the defensive linemen will come hard charging thinking it is a pass, and the linemen directly across from them will bypass them to block a linebacker, while another linemen comes over and basically surprise-blocks them into oblivion. When done correctly, this can open up huge holes.

I already mentioned quick passes. For quick passes, I advocate a simple 6-man slide or area protection, which forces the defense to come from the furthest away to reach the quarterback. Of course, as I said above, some defenses may blitz and bait you into throwing the quick passes, so one must be cautious. But most passing teams will deliver a steady diet of quick passes to any blitz-heavy opponent.

Another approach, most famously used by Texas Tech’s Mike Leach, is to spread his linemen’s splits out wider and wider. The idea, as explained by Michael Lewis (him again):

The big gaps between the linemen made the quarterback seem more vulnerable - some defenders could seemingly run right between the blockers - but he wasn't. Stretching out the offensive line stretched out the defensive line too, forcing the most ferocious pass rushers several yards farther from the quarterback. It also opened up wide passing lanes through which even a short quarterback could see the whole field clearly.

This approach obviously requires offensive tackles with some ability, but the logic is sound: I will make the path to my QB as far for you as possible. And if we run our offense correctly, the ball should be gone. (Remember what I said at the beginning about how most sacks are the result of the QB holding onto the ball too long? Leach has transformed this rule of thumb into a philosophical mantra.)

Finally, the screens. The best modern play in football is the jailbreak screen. (By modern, I mean that it is one of the few genuine innovative ideas in the game, though by that I mean it is less than thirty years old, compared to most of what else we do which is, at minimum, fifty or sixty years old.) Properly executed, it turns a normal offensive play into a kickoff return, uses the defense’s aggressiveness against it, and it is particularly good against zone blitzes, where the play uses the fact that defensive linemen are poor in space to the offense’s advantage.

The screen involves an outside receiver taking a quick upfield step, and then he comes down the line underneath the blocks of inside receivers and the linemen. He cuts the ball up, find the alley, and goes to score. Again, this is probably the best deterrent there is against the zone blitz, as you use the defense’s aggressiveness against it, and those dropping defensive linemen don’t look too good trying to make tackles in the open field. With any luck, maybe it’ll look like one of the jailbreak screens below:


It's only fitting that I conclude with some highlights of the jailbreak screen:





Conclusion

In no way is this article an exhaustive report on the intricacies of pass protection. But it gets us far towards the end. Out of all of football, it is probably the most interesting "mini-game" within the game. The techniques are difficult - pass protecting is an essentially unnatural act that must be learned - and it is the defense that can move around, shift, and redo their alignment at will. Many a passing attack has been grounded from lack of protection. Sometimes from personnel, sometimes from scheme. Hopefully this article has shown how the two work together.

Endnotes/Postscript

* A few notes on the Blind Side and Michael Lewis. I highly recommend all of Lewis’s books. The Blind Side is good, but not as good as Moneyball or Liar’s Poker, though probably much more personal than either. It’s a unique story to football, and a good read.