View Full Version : Guide to N.F.L. Defenses, Part 4: The 3-4 Front

09-09-2010, 06:13 PM
Guide to N.F.L. Defenses, Part 4: The 3-4 Front
Jene Bramel writes for Footballguys.com. You can also follow him on Twitter and reach him at bramel@footballguys.com.

In this installment, we leave the 4-3 front behind and move on to the 3-4, which has quickly become the league’s favored defensive look again after falling out of favor almost entirely during the 1990s. Just as there are multiple flavors of the 4-3 front, there are different philosophies of how to play a 3-4.

It’s not a stretch to suggest that most think first of Lawrence Taylor or the Pittsburgh Steelers’ zone blitz concept when someone mentions the 3-4 front. In truth, the 3-4 has a much richer N.F.L. history than that.

Unlike the 4-3, which was first designed in pro football and first successful there, the 3-4 got its start at the University of Oklahoma in the 1940s (and probably sooner). It wasn’t until the mid-1970s, when teams were looking for ways to contain big speedy running backs and to combat the downfield passing schemes that were gaining favor, that the 3-4 took hold in the N.F.L. as an every-down defense. A number of teams were at the forefront of the 3-4 revolution, but each made the transition in very different ways.

Don Shula and Bill Arnsparger used a three-man line after an injury-filled exhibition season depleted their depth at defensive end and kept it primarily to disguise their coverage looks. The Dolphins called it a “53” after the jersey number of their fourth linebacker, Bob Matheson. The Patriots, under former Oklahoma coaches Chuck Fairbanks and Hank Bullough, used a two-gap concept on the line, preferring to contain offenses rather than risk an overly aggressive approach. Meanwhile, the Oilers were running a much more aggressive one-gap 3-4 under Coach Bum Phillips. All had success.

By 1980, almost three quarters of the defensive schemes in the N.F.L. had three down linemen. As is the case today, there were plenty of variations on the 3-4 theme. There were the aggressive Oilers and Saints under Bum Phillips, the Dome Patrol under Jim Mora in New Orleans, the opportunistic, swarming 3-4 schemes of the Dolphins’ No Name and later Killer Bs, the not-as-aggressive-as-you’d-think Giants of Bill Parcells and Lawrence Taylor, the (original) multiple front schemes of the Orange Crush in Denver and others. Though the philosophies and tendencies varied, the underlying concepts that made the 3-4 popular were the same.

The 3-4 gave coordinators the flexibility to blitz or drop into coverage without changing personnel. Versatile linebackers like Lawrence Taylor or Robert Brazile or Rickey Jackson or Ted Hendricks could rush the passer or drop into coverage effectively. Teams could disguise their blitzes and coverage easily and disrupt the timing and rhythm of the passing attacks that were gaining favor in the league. The outside linebackers could walk up to the line of scrimmage and create a five-man front of sorts to help contain the big, quick running backs of the day. Stars like O.J. Simpson or Franco Harris found it a little more difficult to get outside against the 3-4.

Not surprisingly, the flexibility of the 3-4 front is driving its resurgence today. The versatility of the 3-4 makes it attractive when defending the pass-heavy attacks of today’s offenses, both in the number of coverage and blitz combinations it supports, as coordinators don’t have to rely on the success or failure of the four-man rush. All 3-4 fronts are not the same, however. While the 3-4 front is traditionally thought of as a 2-gap front, there are two major families of 3-4 in use across the league today.

The “True” 3-4

“The 3-4 defense is what the Giants used to play. There was a nose tackle, two defensive ends lined up on the tackles, two outside linebackers and then two [inside linebackers], both covering the guards. One of those linebackers is a fourth rusher. That is the 3-4 — the only 3-4 defense.”

– Charlie Weis, former assistant coach to Bill Parcells

The “only” 3-4 defense? What would Weis call all the other 3-4 schemes in the league today with three down linemen? Granted, it’s mostly an argument of semantics, but Weis (and others) would argue that a true 3-4 defense is one where the three defensive linemen are responsible for every gap on the offensive line – a 2-gap line. They’d call the other variations – which are now much more common than the traditional Bullough-Fairbanks system favored by Parcells – hybrid schemes of a true 3-4, since they frequently use 1-gap alignments that are the hallmark of modern 4-3 fronts.

The first installment of the series detailed the system for numbering and lettering the defensive line techniques and gaps, using Warren Sapp as an example of how a couple of inches of difference in alignment can make a major difference in the responsibilities of a defensive lineman. The differences in how gaps are assigned to the front seven personnel is the key to differentiating between the two major families of 3-4.

Let’s look at the “true” 3-4 first:

Fans have been known to chuckle at John Madden’s description of Parcells’ 3-4 as a “double bubble” scheme, but it’s a good visual and a term often used by defensive coaches. The 2-gap alignment leaves both offensive guards uncovered by defensive linemen – a “bubble.”

Each inside linebacker covers the “bubble” left by the defensive line. This kind of 3-4 requires a specific class of player. The defensive linemen have to be monsters, able to handle the lineman in front of them and control the gap to either side. Ideally, they’re disruptive enough that the guards have to help block them rather than scraping off their double team to block an inside linebacker.

The inside linebackers need to be big enough to take on a guard on every play if the linemen aren’t good enough to keep them clean. Parcells called it the “Planet Theory” – i.e. there are only so many men on the planet big and skilled enough to play 2-gap defensive line techniques in the N.F.L.

To some extent, that theory also applies to the linebackers in a 2-gap 3-4 scheme. Guys like Dat Nguyen sometimes won Parcells over, but he wasted no time in drafting bigger players with a little less speed like Bradie James and Bobby Carpenter and Kevin Burnett to replace smaller players like Dexter Coakley when in Dallas.

Parcells liked the 2-gap 3-4 for many reasons. In addition to the flexibility and versatility arguments above, a three-man front makes it easier to drop eight men into coverage and prevent big plays. It makes it easier for an OLB in a two-point stance to get an angle in pass rushing and generate pressure with just four rushers and avoid the coverage risk of an all-out blitz.

But the 2-gap 3-4 front is more difficult to play in today’s N.F.L. Those planet-like defensive linemen are getting harder and harder to find. Players generated by today’s college defenses are built for speed. Not many defensive line prospects can hold the point of attack against a monstrous OT and control two gaps. Not many 245-250-pound linebackers are agile enough to elude a guard on every play and still run down a ballcarrier with 4.45 speed. With the number of coordinators running the 3-4 now, those players are even hotter commodities than before.

As a result, a majority of the 3-4 fronts today are based on the 1-gap schemes designed by Bum Phillips or those that use other wrinkles to bring pressure and disguise coverage. Other than Parcells’ Dallas and Miami teams in recent seasons, every other contemporary 3-4 defense mixes in 1-gap techniques liberally, some exclusively. The true 3-4 front has become a dinosaur of sorts as an every-down defense.

Bum Phillips and the 1-gap 3-4

To hear Bum Phillips tell it, developing his version of the 3-4 defense wasn’t rocket science.

“Coaching is pretty simple really. If you don’t got something, find something you do got. Really, we didn’t have but one [defensive lineman] – [Hall of Famer] Elvin [Bethea] – until we got Curley [Culp] in the middle of that season. Then we had two. What we did have was four real good linebackers, so all I done was find a way to get our best players on the field.”

Like the Fairbanks-Bullough 3-4 scheme that was taking hold in New England at the same time, Phillips was looking to contain the run and create mismatches in pass rush. Though Phillips based his scheme on the same concepts that the New England coaches did, he favored a more attacking style. He used a number of one-gap techniques in his front seven, stunting and slanting his linemen to cause pressure and using an OLB – “Dr. Doom” Robert Brazile, who was LT before Lawrence Taylor came into the league – frequently as a fourth pass rusher. In many ways, Phillips’s scheme was a 4-3 with four players in a two-point stance.

That attacking style of play has stood the test of time better than the read-and-react style for much the same reason that the 4-3 with an under or over shift has. It allows players to attack the offense, specifically by disguising the defense’s fourth (and fifth or sixth) pass rusher and the coverage behind. In fact, there are a lot of under front concepts in the Phillips 3-4.

In contrast to the true 2-gap 3-4, there’s no clear “bubble” in a 1-gap front. The strongside end slides down in the guard-tackle gap and the nose tackle slants to the weakside center-guard gap. The weakside end may or may not be head-up on the tackle, sometimes aligning in a 5-technique. Moving the defensive lineman just a few inches changes the philosophy entirely. The diagram above shows an under-shifted 3-4, but over-shifted 3-4 fronts are also common.

By comparing the two 3-4 diagrams, it’s easy to see how the mind-set of the defensive linemen differs between the two flavors of 3-4. It’s clear that the two inside linebackers can be, if the linemen are disruptive at all, better protected from the blocks of interior linemen. You can see the lines of attack for a delayed ILB blitz or how each OLB might get a jump by shifting one defensive end to the outside of an offensive tackle.

The under-shifted 3-4 front, with or without a 2-gap end, is just one of many potential variations a coordinator may align for his front seven. In fact, a coach influenced by both flavors of the 3-4 might be tempted to meld both concepts with traditional 4-3 ideas and create a monster playbook with more than 50 fronts. And pull it off with amazing success.

The Hybrid Playbook

There’s no simple diagram or playbook quirk that defines Bill Belichick’s defense. Rather, it might be said that it’s the complete lack of one.

Belichick, in a very short span early in his career, was introduced to many different defensive schemes at the pro level. He was exposed to Maxie Baughan, who ran George Allen’s complex 4-3 scheme, whicht was full of pre-snap adjustments. He briefly coached with Fritz Shurmur, who would follow Allen (and others) as coordinators who frequently used nickel schemes as a base defense. He worked with Joe Collier, who turned a troublesome set of injuries to his front seven into Denver’s vaunted Orange Crush – maybe the original multiple-front scheme.

Those exposures came before he gained fame and respect under Bill Parcells and the true 3-4 in New England and New York.

The key to the success of Belichick’s style is flexibility of personnel. To be able to switch from a 4-3 to a 3-4 to a dime defense and all points in between requires versatility at nearly every position. Players have to be able to run and cover and hit. Linemen have to be strong enough to hold the point in the 3-4, but get upfield in a 4-3. Defensive backs have to be very good in zone coverage but competent in man coverage when needed. It requires special skills, but also an above-average football IQ. Compared with the base Dungy-Kiffin scheme, which probably started with as little as three or four fronts and a couple of zone coverages, Belichick’s hybrid is a maze meant to confuse and confound.

Another important difference in Belichick’s defense is philosophical rather than playbook-oriented. Most coordinators identify the weaknesses of an upcoming opponent and game-plan to take advantage. Belichick specifically seeks to take away the strength of an offense, forcing it to operate out of its comfort zone. In a league where you may face a power offense one week and a spread offense the next, the versatility of the multiple front playbook is the only way to pull off such a philosophy.

Belichick isn’t the only coach with a multiple front playbook. Coordinators like Mike Nolan, Rex Ryan and Dick LeBeau thrive on a confusing mix of fronts, both conservative and aggressive, from which a variety of man and zone coverage and any number of designer blitzes can be generated. In our final three installments, we’ll look at some of the variations that have made the multiple front coaches successful -– the fire zone blitz, the 46 and some interesting subpackage looks built to befuddle offenses and generate big plays for the defense.