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The Voices In My Head Discuss the 3-4 Defense

By CornFromAJar

'Cause if you're gonna have voices in your head, they may as well talk football. Oh, and one of the voices is a complete moron, so just bear with him...

I heard Tennessee used 43 defenses last year, but now they might only use 34. What's up with that? Yeah, no. Last year, and for the last several years, Tennessee has used a 4-3 scheme on defense, which basically uses four defensive linemen and three linebackers (in fact, the Decade of Dominance DVD credits UT with being the first SEC team to employ the 4-3, going to that defense in the early '90s. And they said Johnny Ball wasn't innovative...). What you may have heard is that because of a surplus of good linebackers and a supposed dearth of quality defensive tackles, coach Chavis is toying around with a 3-4 defense, one that uses three down linemen and four linebackers.

Perfect! There's no way to go wrong with that, is there? Well, I can see a couple problems that might come up. But before I get into my misgivings, a better explanation of the 3-4 from Football Outsiders:

The key player in a 3-4 scheme is the lone interior lineman, who is usually called the nose guard or nose tackle. He lines up directly across from the center -- on the center's "nose" -- though he may sometimes shade over to the space between the center and one of the guards. He almost always has two-gap responsibility. His job on nearly every play: force two offensive linemen or more to block him.

The defensive ends in a 3-4 alignment have jobs similar to that of the nose tackle: they want to take up space, fill gaps, and occupy blockers. In a 4-3 system, linemen are supposed to occupy blockers, but they are also expected to free themselves to make tackles and sacks. In the 3-4, linemen aren't expect to make many sacks or tackles. Most of the playmaking responsibilities fall upon the linebackers.

The 3-4 system gives the defensive coordinator a variety of options. At the snap, he can blitz any combination of linebackers, and the offense doesn't necessarily know where the rush is coming from. Typically, one or both of the outside linebackers will attack the line of scrimmage, whether to pressure the quarterback or tackle a running back in the backfield. That leaves two inside linebackers to follow the flow of the play, pursue running backs, or drop into pass coverage.

That's just a small excerpt from a much longer and really good article, but I think you get the idea. To me, the important line there is the first one, "the key player in the 3-4 scheme is the lone interior lineman." It's worrisome to me that if we're needing to switch defenses to hide our crappy DTs, that we'd be switching to one that relies heavily on the DT to make the darn thing work.

I'm confused. Could you clarify through an outdated pop culture reference? Sure. It seems a little like the scene from Days of Thunder, when Harry is explaining to Cole the difference between using tires in NASCAR and using tires in open-wheel racing:

When you were out there driving open wheels, the car weighed half as much and the tires were twice as wide. Now, the car weighs twice as much and the tires are half as wide and you're burnin 'em up.
In other words, in one case -- the 4-3 -- the workload is spread over more area, lessening the stress on the individual parts in case of failure. With the 3-4, you might be able to hide a weak defensive line by having fewer of them on the field, but mistakes are magnified because mistakes mean the linebackers are getting blocked instead of making tackles.

I guess that's why we couldn't we play like a 2-5 or a 1-6? Right, but if you remember the Florida game from 2001, Tennessee ran a funky defense where there were only two down linemen and everyone else, including DT John Henderson, was moving around at the snap.

Oh, so smoke and mirrors, mass confusion and chaos, dog marrying cats, etc.? Some of that, especially the confusion part. So why doesn't everyone use a "funky" defense all the time? Because it's more than a head game. And there's a heck of a lot of nuance to both offensive and defensive formation/alignment that I'm nowhere near qualified or smart enough to discuss. But with all the variations on that theme, all coaches can do is try to put players in the best position to make plays. Once the ball is snapped, it's up to the players to... Make those plays? Right.

Bottom line? Tennessee may switch to the 3-4 out of the gate or may not use the 3-4 at all. Part of the 3-4's fate depends on the progress of JT Mapu and Demonte Bolden as starters and the ability of guys like Walter Fisher to provide depth, because the term "starter" can be a loose one on the defensive line. Ideally, you'd like to have several guys you can rotate in on the line without much drop-off. But if those guys can't play ball, it won't matter what type of defensive front UT uses. Scheme only gets you to the snap, after that our guys better be better than the guys from Cal, or Florida, Georgia, Alabama, etc. Are our Guys better than the guys from Cal, Florida, Bama, etc.? I sure hope so. Me too. Go Vols! Go Vols.

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