4-3 or not 4-3, that is the question (for the New England Patriots)

There's been talk lately on Pats Pulpit about a potential change to the New England 3-4 defensive scheme. Lots of talk.

In particular, it's been talk about whether Belichick and the Patriots organisation will/should scrap the tried-and-true 3-4 in favour of a base 4-3 scheme. Alongside this discussion is talk about whether the Pats should change the roster and scouting to be more 4-3 friendly, as even theorising about selling the house to buy Peppers and re-jig the entire defensive scheme to suit the needs and strengths of Peppers. 

It would all be airy-fairy stuff it it weren't for the occasional comments leaking out of the Pats camp about the problems with the uptake of the 3-4, including this gem from Patriots Director of Player Personnel, Nick Caserio:

One of the reasons those ideals are so hard to find these days — no matter the body type — is that more and more teams are playing a 3-4 defense these days. Caserio estimated that "half the league is employing some 3-4 type of configuration."

"It is becoming more challenging," he said, "because there are more teams that are essentially looking at the same pool of players, so it kind of limits your opportunities, because you realize you’re really competing really with the rest of the league on that front."

It's harder to draft personnel to fit the scheme - more teams are using it, meaning there's competition. Sure, that makes sense. But is this alone the death-knell of the 3-4 in New England? More after the jump...

Belichick's always tried to be one-step ahead of the league in terms of personnel and scheme management. When Bill Polian's -incessant whinging- arguments for a passer-friendly league got the rule book changed to prevent the Pats-style physical bump-and-run defence, did Belichick follow the trend and buy a bunch of WRs to take advantage of the new no-contact rules? No. Did he go out and buy the "I'm-alone-on-Revis-Island-and-loving-it" type-CBs that were now necessary to shut down the passing game? Not by a long shot.

Instead, Belichick bucked the trend completely - he purchased a top-flight running back in Corey Dillon and drafted a run-eating Nose Tackle by the name of Vince Wilfork... and won a Superbowl. And that was in a season where Troy Brown was at cornerback and Andre Davis and Tim Dwight were on the WR roster. When the league changed the rules to suit one kind of offence, Hoodie went the opposite direction and milked the rewards.

So now there's a similar sea-change in the NFL - the rush to install 3-4 defences - there's a chance that Hoodie will again veer off from the path of trendiness and blaze his own trail, this time in the 4-3 or some other variant.

Would I absolutely discount it? No - I'd never discount anything as an option when Belichick is involved. But I don't see it as very likely - I believe Belichick's favoured 3-4 has too many schematic and roster advantages over a 4-3 scheme to justify moving away from it. All of the advantages I see all arguable, of course (and I do expect argument - feel free to poke giant holes in this story. It's how I roll). Anyway, I'll offer a point by point breakdown of the schematic advantages as I see them.

Versatility
Pretty much any 3-4 scheme will have nickel- and dime- based defensive formations. In other words, not only can the 3-4 D-line sub into a 4 man front, they do it regularly. So any 3-4 can easily switch to a situational 4-3 scheme - it's just a case of plugging in the normal nickel front and leaving a linebacker off the field. Voila, there's an extra 300lb run-stopper on the field. 

The reverse is not true. Most 4-3 schemes lack the depth and quality of linemen to situationally sub into a 3-4 front. They don't have (as a general rule) a genuine 3-4 nose tackle. Further, they don't tend to carry the quality athletic big-bodied DE as their second DT - in other words, they're lacking a Richard Seymour-type guy. And even if they have one, they're not going to carry two, meaning the third D-lineman spot in the 30 front is being held by a backup 4-3 DT in a position where you usually want one of your better linemen.

So if you start off with a 3-4, you can easily dial down into the 4-3 and not lose a lot of ability. But if you're a 4-3, sliding into a 3-4 isn't going to happen anywhere near as easily - you're going to have a fragile, undersized nose tackle, and you're very likely to be missing at least one, and maybe two of those athletic, big-bodied DEs. It's not to say it can't be done - the Saints did it on occasion - but considering every 3-4 front can and does adjust to a 40 front on occasion, the odds are against the 4-3 in terms of versatility of the D-linemen.

Roster flexibility
A 3-4 is naturally heavy on linebackers; linebackers are expected to be the big, quick, game-changing guys - Bruschi, Vrabel, McGinest. Yet those guys who made names and won Rings as 3-4 linebackers also made their presence felt in other positions. Bruschi started off as a situational DE/OLB - he was a sub-package situational pass-rusher who evolved into a veteran leader and interception-hungry 3-4 Inside linebacker. Mike Vrabel was a pass-rushing backup DE that morphed into an every-down Outside Linebacker, sometime Inside Linebacker, and pass-receiving goal-line TD-monster Tight End. Willie McGinest was an OLB that was situationally subbed into DE as a pass-rusher and even QB spy. In other words, not only does the 3-4 allow you to stock up on LBs, but it allows and encourages you the flexibility to find interesting and varied ways to use them. What does it prove? That when you've got a 3-4 roster, you can mix and match your personnel and positional requirements to get your people in position to make players - it's flexible and creative, and due to the flexibility is very, very hard to counter.

In contrast, the 4-3 as it is commonly conceived (say, by the Colts) is all about consistency of pressure, every down, time after time. That consistent pressure is delivered by the DEs - it's a scheme that revolves around those pass-rushing DEs to create all the plays. The linebackers aren't tasked to make big plays - they're smaller and are typically coverage guys who are meant to prevent passes by marking players or zones for long enough to allow the DEs to sack the QB. Corners and safeties are similar - it's all about creating just enough pressure on receivers to allow time to hit the QB by the DEs; the CBs are there to milk interceptions from QBs who are under constant DE pass-rush pressure. The 4-3 is all about the DEs - sack, sack, sack.

That's what's meant to happen - DEs to hit the QB, every time. Match-ups don't matter - DEs pass-rush, irrespective. The nature of the opposition doesn't matter - DEs pass-rush, irrespective. Repeat. And repeat. And repeat. Consistency is key, not misdirection, disguise or creativity. It can work; it can work very well. But it needs those DEs to stay healthy - if one of those DEs gets injured, you can't disguise the injury or plaster over the cracks, you can only plug in the (sure to be less able) replacement, and hope everything goes okay. 

If the 3-4 has injury issues, you can lean on that inherent flexibility of a Linebacker-oriented roster - say hello to the Chaos package, for instance - 7 LBs on the field at once with no linemen. Huzzah! Or stack OLBs at DE if you're low - Ninkovich and Burgess at DE? Yup, did that. Slot a 300lb DE into NT and watch it tick along nicely? Mike Wright, ladies and gentleman. Got an annoying opposition LT to counter? Wilfork at RE, please. However, when your'e in the 4-3, you're stuck with what you've got. DEs pass-rush. And pass-rush. And pass-rush. If your DEs aren't hitting the passer, your season is tanked - 2009 Giants, take a bow. 

That's not to say the 3-4 is an automatic fix - 2009 Steelers fans wouldn't agree with that proposition - but by the same token, their coaching staff didn't lean on their roster flexibility - they didn't try a Chaos all-linebacker front, for instance. When the Pats had a nicked up D-line they threw a half-dozen LBs on the field and confused the opposition silly; when the Giants and Colts D-lines were hurt, it was game over.


Durability
Basic fact - mass times acceleration equals force. And when it comes to collisions, you want to be the guy dealing out the force, not taking it. When all NFL players have similar-ish acceleration - the Combine proves this pretty much every year - then that means mass is king, and that's why 300lb+ 3-4 D-linemen are more durable than 4-3 260lb 4-3 DEs.

It becomes even more apparent over a long season, especially because 4-3 D-linemen are never meant to come off the field. Think about it. 4-3 DEs are usually the standout defensive players on their team - Mathis, Freeney, Allen, Peppers, Strahan, Umeniyora. So you really, really don't want to take them off the field if you can avoid it. They should be there on first and second down - that's when you want to stop the run and prevent any big plays, holding the opposition to long yardage. And then you need them on the field for third down, because they're your best pass-rushers - Strahan didn't get sack records because he trotted off the field on third downs. That means you've got a 260-270lb guy wrestling gigantic O-linemen on every single down that he's physically capable of playing - that has to hurt over a while.

In contrast, 3-4 D-linemen aren't every-down guys, nor are they meant to be. Even sometime team sack-leader Richard Seymour went off on third-down; the Pats would dial in their sub package of guys like Tully Banta-Cain or Rosie Colvin or Willie McGinest, who are pass rushing linebacker/DE hybrids. The ability to take off your linemen on every third play means they get hit fewer times, that you can pick and choose matchups to suit your personnel, and you can generally let your D-linemen get rest and physiotherapy that much more easily over the entire season. That really helps - you want your linemen healthy for January and (hopefully) February, not just November and December.

And when those 3-4 D linemen do get hurt, they're less critical to the team's plan. The Pats won a Superbowl without Richard Seymour for most of a season; in 2009 they coped pretty well with Seymour being traded at the last minute to Oakland, with Jarvis Green, Ty Warren and Vince Wilfork all being injured at various points, and with plugging in rookies like Myron Pryor and Ron Brace into the lineup. The positions on the D-line of the 30 front are less specialised than on the 40 - DEs can be interchangable with Nose Tackles (Wilfork played RE against the 'Phins and Mike Wright subbed in at NT when he wasn't starting at RE or LE). Compare that to the 40 front - going to be brave enough to put Dwight Freeney at DT? Want to see Tommy Kelly's awesome spin move (cough) at RE? Not so much. So as long as you've got 3 able-bodied D-linemen, you can put up a 3-4 defensive line that will work; the same can't be said of the more specialised 4-3 linemen. 

Bearing in mind the length of the season, the likelihood that smaller guys will pick up more injuries than bigger guys, and that 4-3 linemen are harder to replace and back up, it's no surprise that the injuries occur at the business end of the season. Consider this - the 2009 Colts D-line suffered one injury prior to the Superbowl; Dwight Freeney hurt his leg in the Conference game. And that one injury to one leg severely damaged the Colt's chances. Not only was one of their better backside pursuit run-stoppers slowed down due to injury, but their best pass-rushing weapon was hurt. That's a lot of injury to the team resting in one gammy leg.

A significant part of the Colts' defensive firepower was brought down by that one injury. And it had flow-on effects - when the Saints realised Freeney wasn't a threat, they slid a lot of the O-line's coverage across to Robert Mathis and took Mathis out of the game, too. In short, one leg injury meant almost all of the Colts' pass-rushing ability was negated - no Mathis and no Freeney. Cue Drew Brees throwing a completion rate of 90% or so (if you take out the outright drops by WRs). Ugly.

Longevity
It's common knowledge that 4-3 Linemen get smacked around. Hell, that's why Julius Peppers wants to go to somewhere with a 3-4 in the first place - he knows he can squeeze another couple of years out of his body by being a 3-4 OLB rather than a 4-3 DE, because he knows OLBs get hit less often. This is in part due to how you use a 4-3 DE - they're meant to be every-down guys, constantly trying to run into/around bigger O-linemen, and often running smack-bang into TEs and HBs if they do get around their blockers. 3-4 OLBs aren't like that. They drop into coverage or slide into the flats, they cover man-on-man, they can edge-rush or bull-rush, and they can do it from any angle. So a 3-4 OLB of a similar size, height and weight ought to stay more healthy than a 4-3 DE.

Now, look at the 3-4 D-linemen. 3-4 DEs might arguably get into more contact than 4-3 DEs, but it's not the same type of contact. They aren't going to run into Offensive Tackles at full-tilt, every down; instead they'll try to wrestle aside double-team blocks that they enter from a foot or two away. It's the difference between standing at an arm's length to a brick wall and trying to push it over, and running into a brick wall from a 5 or 6 foot run-up. One is hard, the other is painful. Now do it every single down and it's no wonder you risk getting hurt.

And those same 3-4 D-linemen have an added advantage over their 4-3 brethren - they regularly get subbed off on passing downs. 4-3 DEs are the best pass-rushers - they stay on the field for third down as long as they're standing. 3-4 guys are line-cloggers; they get subbed off for Banta-Cains or McGinests. That means they get time to rest, repair themselves, get injuries seen to. It also means they also suffer a lot fewer collisions because they're not on the field on every down - that has to help their health. So when Julius Peppers wants to get out of the 4-3 to prolong his career, he's showing a remarkable amount of foresight - 4-3 DEs get punished.


Replaceability
Every 4-3 front has two defensive tackles. Obvious, right? Yet those tackles come from the same stock as 3-4 DEs - the big bodied, immensely strong college DT cadre. So when you think about it, coming across a potential 3-4 DE or NT isn't too hard - there's at least 2 or 3 potential 3-4 DEs or NTs on every single roster. Not all of them would work, of course - some wouldn't be big enough to work the Nose, some of them wouldn't be athletic enough to be a good DE - but there's so many of them, that you'd at least have a shot of finding someone who'd work well. And when you use the argument that "now half the league is using the 3-4, it's going to be harder to find personnel", that only works if you're only talking about drafting guys. Sure. You're competing in the draft with a bunch of other teams for the same type of player. But if you flip that, that means that one out of every two teams has the kind of guy you're looking for. You can steal their free agents. You can trade for their players. The more teams that run the 3-4, the more 3-4 type players are going to be around and have NFL experience. The Patriots aren't the Colts or the Steelers - they have no qualms about trading for players who fit the system or picking guys up in free agency. In other words, the more teams that run the 3-4, the more players there will be who are familiar with the concepts. That's a good thing, not a bad one.

The list of comparisons between the two systems is endless - I'm sure we could all be bored silly with endless discussions of personnel packages, substitutions, comparisons of 2-gap, 1-gap, 3-, 5-, and 7-technique linement, etc. But when it boils down to it - the Pats expect (legitimately) to get the the playoffs most years. And they want to go deep into the playoffs when they do. That means you want (a) a healthy D-line in January-February, (b) a productive D-line in January-February, (c) enough depth and strength of numbers to be able to cope with any issues in (a) or (b), and (d) a defence that isn't geared around the health and ability of only one or two players, just in case they get injured.

To me, that only really leaves the one option - the 3-4. Having all your hopes, production and ability tied into the health and welfare of only two guys - 4-3 DEs - just seems too optimistic to me. I'd much rather rely on having a fair number of interchangable players with strength and size on the (crowded) depth chart rather than a pair of phenomenally fast, skilled and gifted defensive players on the roster. However, that is merely my opinion. Feel free to convince me otherwise. Fire away.