Happy Tuesday, friends. As promised in my last article, today, I want to propose a proposition. I think that it’s high time that people stop acting like there are only two kinds of defense being played in the NFL, and that we come up with a better way to identify them.

You’ll recall that last Tuesday, I made the case that the base personnel grouping (3-4 or 4-3) was not only not determinative of the character of a defense, it’s actually only barely relevant to the discussion. It doesn’t necessarily contain any indication of tactical approach, so saying that a team runs a 3-4 defense means almost nothing, yet that's all you get from the football commentariat. This injustice will not stand, man!

On offense, at least, the traditionally recognized groupings speak to tactical approaches. When somebody says that a team runs a West Coast offense, you tend to think of horizontal passing, and timing routes, and a running game that sets up that kind of passing. The basic principles are mostly common within the group. That isn’t the case for a “3-4 defense” or a “4-3 defense,” not at all.

I think the reason for that is that defenses are generally much less verbiage-heavy, so less goes into the learning process for the terminology. For that reason, defensive coaches tend to be more easily able to cobble together specific tactics that worked from a bunch of different schemes during their career, so every resulting defensive scheme ends up being a mix of stuff.

That’s somewhat true of offenses too, but because offenses tend to be imagined and set up as interconnected frameworks, you tend to get more faithful adherence to schematic principles, as they pass through the generations of coaches.

The other reason for the insufficient naming convention in defensive schemes is that when people watch football, they watch the ball. Their view of the game is from the perspective of the offense, so it’s easier to tell what they’re doing in real time, than it is to tell what a defense is doing.

Why can’t we have a defensive naming convention that actually imparts what a defense does? Is it too difficult to figure that out, and to disseminate it? I don’t think it is, and today, I’m going to propose a new model for talking about and understanding defenses.

In psychology, there’s a model called the Myers-Briggs Type Indicator (MBTI) that’s pretty widely used and understood as a useful method for identifying personality types in a general way. There are four dimensions of personality used in the model, which was based on work done by Carl Jung, and each dimension is dichotomous, with only two possible states of being:

(E) Extroverted vs. (I) Introverted

(N) Intuition vs. (S) Sensing

(T) Thinking vs. (F) Feeling

(J) Judgment vs. (P) Perception

Everybody comes out of the test as one of 16 possible types. I’m an ENTJ, which, after you read that Wikipedia article, you could all probably guess from reading my work. I was an ENTJ at 18 years old, and I was an ENTJ at 35 years old. I’m sure I’ll be one when I die too. We are who we are, and for the most part, people don’t really change that much.

They say there are two kinds of people – those who dichotomize, and those who don’t.

Well, I tend not to be much of a regular dichotomizer, because usually, there are more than two possible states of being. I think that the MBTI did a pretty good job of identifying personality traits where there are two defined ends of a continuum, though, and where everybody falls somewhere in that continuum.

That’s the kind of situation I find with football defenses, and I like the idea of employing four dichotomous dimensions for understanding them. It’s a manageable number, and a maximum of 16 possible groups isn’t too many. I believe that if we set up and use such a model, we can add that information to the base personnel grouping (or not), and we can really describe what a defense looks like, and what it likes to do when we talk about it.

In that vein, today I introduce the Defensive Scheme Type Indicator (DSTI) and submit it for your consideration. (I almost named it the Bartlett Defensive Type Indicator, like Myers and Briggs did, but I get enough crap about being full of myself already, so I decided to humble it up.)

Dimension 1 – Front Play

(S) Stack vs. (P) Penetrate

Much more important than how many defensive linemen have their hands down is the consideration of what they’re doing. Tactics are more important than alignment, and the truth is that alignment varies a great deal within all defensive schemes.

Another term for stack is “two-gap.” The defensive lineman who is two-gapping will tend to align in an even-numbered technique, head up on an offensive lineman, so that they can engage the guy, try to stand him up, and play both gaps to either side of him. You know how defensive ends in 3-4 schemes are often called “five-techniques?” More often than not, they align as four-techniques, head-up on the OT.

A scheme that is looking to penetrate can be said to be playing a one-gap approach. The linemen will tend to align in odd-numbered techniques, which will put them directly in gaps between offensive linemen. At the snap of the ball, they’re trying to penetrate that gap, and get in between those linemen.

Dimension 2 – Run Game Orientation

(D) Downhill vs. (F) Flow

This is a question of how defenses combat a running game, and that tends to come in two flavors. In both, there’s an accounting that happens for eight gaps, but there’s a significant difference in how the cat is skinned. That difference plays out mainly in the type of linebackers you need.

Most of us have heard the term downhill running, and what I mean by downhill run defense is that the second-level defenders (linebackers and often, a safety) are aggressively filling run fits, and trying to get upfield first, and ask questions later. In a downhill gap containment concept, it’s all about winning the battle in as many gaps as possible, and giving a running back nowhere to go. The benefit is that you can more often win the run game battle when you guess right; the downside is that you make yourself extra-vulnerable to play-action.

A flow approach, on the other hand, calls for defenders to stay back a bit, read the play as it unfolds, and then run to the ball and make the tackle. This approach favors defenders with range and quick recognition ability. It’s a bit less aggressive in nature than a downhill approach, but once the defender makes his read, it gets pretty aggressive.

Dimension 3 – Coverage Orientation

(M) Man to Man vs. (Z) Zone

Here’s something important that’s addressed not at all in the standard 3-4 vs. 4-3 nomenclature – what is a team doing in coverage to stop passing games?

This is a fairly simple distinction – does a team defend the pass primarily with man coverage or zone coverage? The question has a lot of implications for personnel acquisition, but one thing it doesn’t signify as much as it used to is how often the defense will blitz. Many zone teams now play fire-zone schemes, and blitz as frequently (or more) as predominantly man-coverage teams.

One thing I want to say in this category is that the type of zone that teams play is less important than whether they play man or zone. You’ll hear a team called a Tampa 2 team, and that’s somewhat descriptive, pointing to one specific wrinkle - the MLB carries an inside receiver down the field and basically ends up playing a deep third, making Tampa 2 really an uncommon version of Cover 3. The principal type of zone isn’t important enough to rate its own dimension, though, even if it does have a catchy name.

Dimension 4 – Pressure Orientation

(B) Blitzing vs. (C) Coverage

This is probably the easiest dimension to discern from watching a game as a casual fan – how often does the team blitz? It’s a very important consideration if you’re trying to get to the character of a defense.

Think about it like this – If a defense is rushing four men, which is standard, they have seven men left over to defend the pass in some way. Are they more often bringing extra rushers beyond the four? If they are, we’re going to call that a blitzing team for this purpose.

If the defense is mostly dropping seven men into coverage on passing downs, we’re going to call that a coverage-focused team. Of course all teams blitz sometimes, but the ones which favor soundness in coverage more often than not are going to be C’s.

Where do NFL teams fall?

I went ahead and categorized all 32 teams based upon my own perceptions of their defensive tactics. This is subject to change, for two important reasons:

I admittedly don’t watch as many games as I used to in 2009 and 2010, so I’m less sure of every team, and I’m not claiming to be all-knowing across the whole league. (If it were my fulltime job, I absolutely would be, though.) With coaching and personnel changes, a lot of this is going to be fluid as we enter the regular season, and will need further observation.

Here are some observations of the groupings, beginning with a look at how each dimension breaks down.

Dimension 1 – Front Play

I’ve identified 17 teams as (P)enetration teams, and 15 teams as (S)tacking teams. Traditionally, 3-4 teams have taken more of a stacking approach, and 4-3 teams have taken more of a penetration approach. That mostly holds true here, with the following seven exceptions:

4-3 teams who scheme to stack:

Denver, Miami, New England, Seattle

3-4 teams who scheme to penetrate:

Buffalo, Houston, San Diego

You’re starting to see why “3-4” and “4-3” are insufficient identifiers, right?

Dimension 2 – Run Orientation

I’ve got 14 teams playing a (D)ownhill style of run defense, with seven each coming from 3-4 and 4-3 schemes. That leaves 18 teams playing more of a lateral (F)lowing style of run defense. Ten of those teams play in a base 4-3, and eight play in a base 3-4.

Dimension 3 – Coverage Orientation

I have 14 teams playing primarily (M)an-to-man coverage, and 18 teams playing primarily (Z)one. The up-front personnel grouping is (again) not particularly determinative of which type of coverage each team favors. For the M group, there are eight 3-4 teams and six 4-3 teams. For the Z group, there are seven 3-4 teams, and eleven 4-3 teams.

Dimension 4 – Pressure Orientation

For our final dimension, I have the clearest split, and the only one where you might say that a meaningful majority of teams favors one tactic over another. I’ve identified nine teams as playing (B)litzing-oriented schemes, with seven of them playing a base 3-4 front. (Note that I don’t count the fourth rusher in a 3-4 as a blitzer, no matter where he comes from.) The 4-3 teams I consider to be blitzing-oriented are the Seahawks and Eagles, and I consider both to be close to the middle of the continuum, and just slightly to the B side.

That leaves 23 teams as being coverage-oriented, with eight coming from the 3-4 group, and 15 coming from 4-3 fronts.

Looking at the total groupings

PDZC – Penetrating, Downhill, Zone, Coverage – 6 teams

Carolina Panthers (4-3)

Dallas Cowboys (4-3)

New York Giants (4-3)

St. Louis Rams (4-3)

Tampa Bay Buccanneers (4-3)

Tennessee Titans (4-3)

This is a big group of teams that play a lot of Cover 2 and Cover 3 zone. I’m going to be watching Tampa Bay and Dallas closely, because I could see the Bucs using more man coverage with Darrelle Revis in tow, and because I could see the Cowboys going to more of a flowing run defense.

PFMC – Penetrating, Flowing, Man, Coverage – 4 teams

Cincinnati Bengals (4-3)

Detroit Lions (4-3)

Jacksonville Jaguars (4-3)

Oakland Raiders (4-3)

These are some aggressive defenses up front, but ones which primarily are trying to get pressure with their front fours. The only one of the bunch with any current quality in their secondary is Cincinnati, but all four teams would like to be sound in coverage through their scheme.

PFZC – Penetrating, Flowing, Zone, Coverage – 5 teams

Atlanta Falcons (4-3)

Buffalo Bills (3-4)

Chicago Bears (4-3)

Houston Texans (3-4)

Minnesota Vikings (4-3)

These defenses tend to be pretty similar to the PDZC group, but they’re oriented toward handling the run game by flowing from sideline-to-sideline. Here are still more 4-3 teams, and a couple of 3-4 defenses that play more like traditional 4-3 defenses.

SDMC – Stacking, Downhill, Man, Coverage – 1 team

Kansas City Chiefs (3-4)

I’m speculating here a bit, but I think that the Chiefs are going to probably play a lot of man coverage after signing CB Sean Smith to pair with Brandon Flowers. My understanding is that DC Bob Sutton plans to install a pretty traditional Fairbanks-Bullough 3-4 scheme for his front.

SDZC – Stacking, Downhill, Zone, Coverage – 3 teams

Indianapolis Colts (3-4)

New England Patriots (4-3)

Washington Redskins (3-4)

The Patriots play a hybrid scheme up front that shifts between 4-3 and 3-4 depending on which players are available and healthy. Washington plays a pretty traditional F-B 3-4, and both teams tend to play a lot of zone on the back-end. With the Colts, it’s hard to tell what they want to be on defense, because it seemed like they were just doing what they could with the below-average personnel they had in 2012.

SFMC – Stacking, Flowing, Man, Coverage – 3 teams

Denver Broncos (4-3)

Miami Dolphins (4-3)

San Francisco 49ers (3-4)

These are teams that are trying to play seven in the box against the run game, and then playing a lot of man coverage behind that. For both the Broncos and the Dolphins, the key guy to the success of the run defense is the closed-side DE (Derek Wolfe for the Broncos and Jared Odrick for the Dolphins). If that guy can command a double-team, and win a lot of times, the safety isn’t going to have to come into the box much, and the pass defense will be maximally sound against play action.

SFZC – Stacking, Flowing, Zone, Coverage – 1 team

Baltimore Ravens (3-4)

As I said last week, the Ravens are quite similar defensively to the Broncos, except that they favor more zone coverage on the back-end.

SFMB – Stacking, Flowing, Man, Blitzing – 3 teams

Arizona Cardinals (3-4)

Green Bay Packers (3-4)

New Orleans Saints (3-4)

We’ve come to the beginning of our group of blitz-happy teams. I put the Saints here on an assumption that Rob Ryan will want to do Rob Ryan things. The Packers and the Cardinals both have shown over the last few years that they like to bring pressure from all over, particularly the inside.

SDZB – Stacking, Downhill, Zone, Blitzing – 1 team

Pittsburgh Steelers (3-4)

The Steelers have been doing the same stuff on defense for about 20 years now, and it’s a very interesting mix of aggressiveness and reactiveness. They play the run with a tremendously aggressive downhill style, where the linebackers are taught to run hard to their gaps, and fill as hard as possible. They’re doing that behind a two-gapping defensive line, though, and it makes for a unique approach.

On the back end, the Steelers use zone blitz tactics more than anybody in the NFL. They usually rush five men and drop six, with three defenders underneath, and three on the back end. Over recent years, really since Mike Tomlin came to town, they’ve mixed in a good deal of quarters coverage too. Quarters is basically a hybrid of zone and man principles, and you can read about it here.

PFZB – Penetrating, Flowing, Zone, Blitzing – 1 team

Philadelphia Eagles (3-4)

This is a total guess based upon a few clues. The defensive coordinator is Billy Davis, and he’s favored a penetrating 3-4 scheme in the past, that featured flowing linebackers. The Eagles’ defensive line group has a penetrator (Fletcher Cox), and a couple of two-gappers (Isaac Sopoaga and Clifton Geathers). The OLBs are really defensive end-types in Trent Cole, Brandon Graham, and Connor Barwin.

Davis liked to play man coverage during his time in Arizona, but I don’t think he has man corners right now, so I’m judging this as being probably a zone team right now. I’m calling it a blitzing group because I think they’ll want to have all three of those OLBs rushing a lot of the time, and also because I think Mychal Kendricks has some ability as a blitzer too.

We’ll see how it plays out in the early season, and adjust accordingly.

PDMB – Penetrating, Downhill, Man, Blitzing – 1 team

San Diego Chargers (3-4)

I’m assuming that the Chargers will be similar to last year with defensive coordinator John Pagano returning. Really, their defensive staffing and style dates back to Wade Phillips in the mid-2000s. The defensive linemen tend to be penetrators, and their linebackers fill hard downhill in the run game. The Chargers like to play man coverage, although they probably lack the corners to do it very well right now. They also blitz a good deal in the passing game.

SFZB – Stacking, Flowing, Zone, Blitzing – 1 team

Seattle Seahawks (4-3)

This is the most difficult team in the NFL to categorize, because they do a bunch of everything. Really, the only dimension I’m super-comfortable with is flowing. I went with stacking, because the Seahawks like to play two-gap on the closed side, and use a big DE in Red Bryant, similar to how the Broncos and Dolphins use Wolfe and Odrick. I slightly leaned toward zone, because the Seahawks do play a lot of Cover 2 and Cover 3, but they also use plenty of man coverage, so it’s a tough call. Blitzing is basically a projection based on the reports that the Seahawks are moving Bruce Irvin to SLB, presumably to try to emulate what the Broncos do with Von Miller there.

The future of DSTI

You can now consider Defensive Scheme Type Indicator to be a go-forward staple at IAOFM, at least when I’m writing. I plan to continue to use this method of categorizing and describing defensive schemes, and I’m hoping that we can get it out into the football vernacular, at least among writers who know any football.

I’m open to suggestions and discussion, both about the methodology, as well as how I’ve categorized this team or that. This is a work in progress, and we’ll be revisiting it during the season, maybe quarterly. We’ll update the categories as needed, and maybe I can get Doug to see if there are any relevant statistical observations among the different categories.

My hypothesis would be that there’s no right answer to what kind of defensive framework a team should employ, but maybe that can be proven wrong. It will be fun seeing how it shakes out as the season progresses.

I'll probably never get a know-nothing wanker like Bart Hubbuch to be comfortable using this kind of model, but there are a growing number of good football writers out there who actually know something about football. This is for them, and this is to help advance the dialogue and understanding of the most popular sport in America.