"The defensive end to the tight end side needs to be a defensive player that can play the run. He does not have to be a big time pass rusher, but he has to play the C gap and stop the run. [He] must work for leverage and force and allow the Free Safety to work off of the him and fill where he is needed on run plays."

"The best pass rusher on the team is usually the defensive end to the open side of the field. That puts him on the quarterback's blind side and makes him a C gap player in this defense. We often align him wider than this in order to give him a better angle of attack and allow him to play in space. We align him a yard outside of the offensive tackle most of the time. He has to play C gap run support but at the same time he is rushing the passer like it is third and ten. He has to be able to close down however if the tackle blocks down on him. (He) has to be one of your best football players. Size does not matter as much. We want an athletic player who can move around." - Pete Carroll

One of the most important things regarding Xs and Os - especially within the context of an outsider's point of view - is that a lot of what I have been explaining is simply speculation. I can put in as much research as I want into looking at film, I can read countless articles regarding Pete Carroll's history in the league, but in the end, unless I have the written playbook and philosophy by my side, a lot of the discussion and definition is up for debate.

I thought it was interesting how Beekers commented on the last article that this hybrid defense wasn't exactly a mixture of 4-3 and 3-4 concepts, but rather a combination between philosophies of 4-3 and 3-4 via different gap control and responsibilities. Even the terms "4-3" and "3-4" may sound a bit redundant now in the NFL, as defenses are so focused on moving and using unique players all over the field more that there isn't a "base" D a team usually rely on.

So, I like to begin this part of the series will start with a few changes and clarifications on the last three articles - namely because after looking back at the tape and comparing my notes with those of Beekers, the Seahawks defense is really a lot simpler than what I originally believe. I thought Carroll's definition of "Our defense is a 4-3 scheme with 3-4 personnel" was pretty self-explanatory; the Seahawks just play the 4-3 scheme with 3-4 type players. They have a 3-4 End type player in Red Bryant on one side and a more athletic, traditional 4-3 pass rusher in Chris Clemons on the other. They spell the 1-Tech with looks as a 3-4 Nose Tackle. This is where the terms "hybridization" and "versatility" come into play.

But one of the problems that comes with this definition is the idea that Carroll, as innovative as he seems to be, is still a traditionalist at heart. As he said with regards to the 4-3: "I have been running that same base defense since 1977 when I learned it from (Monte Kiffin). I have used variations of this defense my entire career. I have stayed with its principles through all my years of coaching. I have a real strong belief in this defense. I know the defense and its adjustments so well that my belief system in it is strong and rock solid."

So while the players may continue to fit the 3-4 philosophy as we see it, to Carroll they must be 4-3 players first and foremost, and they must play the 4-3 first and foremost. Just because K.J. Wright can play as a 3-4 OLB doesn't mean he will, and because of that, I believe Carroll's reference to "3-4 Personnel" is a lot more vague and open that what we define it as.

This ties in with the unique roles of Bryant and Clemons and the fact that they are factors of the scheme they play in, rather than the other way around. To clarify, they are fit into the positions Carroll placed them; they don't necessarily define the defense in terms of what it is even if they seem to be. Consider the 2010 season, where, under their first year of a barren roster, the Seahawks essentially held out an open audition for the entire defensive line. Before Bryant was experimented with at the 5-Tech by Dan Quinn, and Clemons acquired by a trade, the Seahawks had planned to slot in Aaron Curry at the LEO and Lawrence Jackson at 5-Tech. (And yes, this was the reasonable and understandable combination.) After all, Jackson had previously played the same 5-Tech at USC, and Curry had the speed and athleticism to at least fit the prototype of a LEO.

Yet neither of them were true 3-4 players, and are even limited to roles for the 4-3 today. This tells me that while Carroll longs for hybrid-capable players on his team, the 4-3 is the core to the defense and that implementing the 3-4 is almost akin to an "add-on" rather than a central part of the scheme. A comparison would be the Seahawks offense and the read-option; it's only there because Russell and Marshawn can run it, and it's really successful, but it's not what the playbook is based.

Finally, the general idea of mixing 4-3 concepts with 3-4 personnel is an ambitious, if not difficult endeavor that requires specific knowledge of both defenses; but even with the history that Carroll has assimilated over the years there wasn't exactly a true understanding or usage of the 3-4. Remember that the only true instance where we see Carroll had been forced to adapt the latter scheme was in his New England years, and in practically every other coaching role or team before and after those years, a 3-4 wasn't even considered or touched upon.

So to summarize, the Seahawks defense isn't really a hybrid. It's not as black and white as playing the 4-3 with 3-4 personnel, rather it's the utilization of several different basic gap responsibilities that creates somewhat of an illusion of a hybrid 4-3/3-4 look, and more importantly, confuses the heck out of opposing coaches (and people like me, who try too hard in understanding what it means).

Let's break it down into simpler terms. The most common and usual 4-3 defenses utilize one-gap techniques and breakdowns on the front four - you have four defensive linemen lining up in a gap, and each man has their own responsibility with said gap.



Now in the 3-4, there are three defensive linemen who take up two gaps with their positioning - and usually line head-up instead of a shade to take advantage of this responsibility:

Here's the catch though; does gap responsibility dictate what type of defense you line up in? While two-gapping and one-gapping are the norm for the 3-4 and 4-3 respectively, we must keep in mind this is only a small piece of the overall puzzle; it does not necessarily affect, say, the number of DL's or LB's line up on a snap or the mentality behind the scheme itself. Remember Carroll's statement: "I run (my 4-3 defense) with one gap principles but can also make it work with some two gap principles." I.e. "This is a 4-3 defense with 4-3 philosophies, but we can also play it like at times like a 3-4." It doesn't necessarily mean that they run a 3-4.

We also consistently hear how the Seahawks like to be aggressive in the front four, which is why Carroll has been preaching that the line must attack within the first snap rather than having to read-and-react. So how does a player necessarily "attack" the line when he is asked to two gap? More importantly, where do you draw the divide between one-gapping and two-gapping, and who on the defense should be given the responsibilities?

Let's re-read Carroll's quote again:

"I run (my 4-3 defense) with one gap principles but can also make it work with some two gap principles. In principle we want to give our players a chance to know exactly what they have to defend. We also want to give them an attitude in which to do that. We want to be an attacking, aggressive football team. We don't want to sit and read the play like you often have to with "two-gap" principles of play. We want to attack into the gap at the snap, get off the ball to play on their side of the field and get after the quarterback." The big problem with any "one-gap" approach however is that it allows a ball carrier to get into the secondary if one guy makes a mistake. No matter how aggressive the defense is there is a great amount of discipline that goes with this defense. You have to be very strict about your positioning and the placement of your players. You have to have the ability to maintain relative spacing between your players." (Emphasis mine)

Carroll's defense is perhaps designed to have an equal balance between one-gap and two-gap philosophies, and the switch between the two is a large reason why Bryant and Clemons play the way they do. Similarly, because the composite of the scheme is between gap responsibilities and not 4-3/3-4 philosophies, it doesn't necessarily restrict the players to be athletic specimens that can play both defenses. It's all about gap responsibility and control, and the "hybrid" factor is only a moniker that stems from this beautiful, but simple amalgam.

And what better way to explain this but from the perspective of the LEO and 5-Tech?

Now it's easy to assume that because both positions are near opposites of each other that one position refers to a 4-3 defensive standpoint while the other refers to the 3-4. This is not true; both the LEO and 5-Tech are fundamentals towards the 4-3 philosophy itself. For instance, the LEO is a standout, athletic pass rusher who needs to be able to play the edge well and rush the passer. The 5-Tech should be able to play the run and work off having the tight end to his side of the field. These are traditional philosophies rooted in the 4-3.

But Carroll then twists the LEO and 5-Tech into something extraordinary by putting Clemons and Bryant at those spots, respectively. In Clemons, the position sacrificed size for athleticism, but it allows him to line up wider on the offensive tackle during snaps, especially on passing downs, to give him a better pathway to the quarterback. (I also partially believe it's because there's a lack of dominant 4-3 ends in the league, i.e. Julius Peppers or Jared Allen, and the wider angle helps pass rusher's ability). More importantly, this fundamentally improves the attacking concept behind the 4-3, because the LEO, with Clemons's relentless speed, is more akin to a linebacker consistently blitzing rather than a defensive end.

In contrast, the 5-Tech, with a bigger player in Bryant, allows for an easier attack towards the tight end crashing down towards the run, and for a size mismatch if placed in a one-on-one against either player:

However, we must keep in mind that these are perks given with a player like Bryant and Clem, and not necessarily an important trait within the LEO and 5-Tech themselves. Likewise, their respective weaknesses - Bryant with a less developed pass rush than a traditional 4-3 defensive end, Clemons being overrun on a counter or trap - must be compensated frequently. This is why Carroll often rotated Jason Jones or Greg Scruggs at 5-Tech frequently on passing situations, and why Kam Chancellor usually dropped down for run defense towards the LEO side and acted as a 4th LB.

Which brings us back, coincidentally, into gap control. Danny wrote a great piece here referring to how the Seahawks run defense struggled without discipline. Carroll himself reiterated that "in principle we want to give our players a chance to know exactly what they have to defend", something which outlining gap responsibilities to each individual player is vital to the its success.

Let's look back to the 4-3 under to see what I mean:

Even though the Seahawks is considered "unorthodox" and "unique", keep in mind this is still a 4-3 defense with primarily 4-3 players. As such, like the first diagram I placed above all gaps are accounted for by the front line. We can also above that it's very clear that the LEO is one-gaping towards the C gap and has outside contain (again, sort of like your prototypical Julius Peppers or Jared Allen.) So aside from the wider angle and the new nickname, there's nothing new to see here.

But on the other side, the 5-Tech is two gapping and, along with the SAM is playing at a mid-level between the LB's and the DL's, it appears the defense is playing a 3-4 (at least from the OL's perspective)...

...when in fact, however, the 5-Tech still maintains control of the B and C gaps (like he would in a 4-3), while the SAM still continues have the outside and contain (again, like a traditional 4-3). Consider how the defense would look with this offensive scheme under a 4-3 over, which is more traditional:

You can see in both pictures how the mentality of the 5-Tech doesn't change, just his gap responsibilities. Yet towards the offense's eyes, it seems Bryant is playing two different positions within two different schemes. Like Russell Wilson with the read-option, Red Bryant's two-gapping is designed to make you over-think and over-scheme and confuse you, when in fact it is just a matter of positioning that is just the outlying difference.

Bryant two-gapping also lets the SAM free up in terms of run and pass responsibilities; because the 5-Tech has to play both the inside of the tackle and his outside/contain, the SAM is given more range and flexibility towards reading the play. In the 4-3 under for example, if the offense starts to run a sweep or outside handoff towards the TE's side, the SAM can trust the 5-Tech to maintain leverage of the C gap, giving him more time to read the TE or the backfield to see if it is play-action or not. As I break it down further here:



So who can play where? Cliff Avril with his edge-around ability seems like a natural fit for the LEO and will probably start there if the team decides to PUP Chris Clemons. Michael Bennett seems more of a natural 5-Tech to me, though he can backup as a LEO as well. In the last article a lot of people commented that I had underrated his run defense, which in my opinion is more relevant and stronger as an exterior DL rather than an interior one. Bennett's experience in Tampa Bay led him to play some two-gapping and as an edge rusher. Jesse Williams is a good 5-Tech development that has the size of Bryant but not necessarily the agility. I would think, with Bruce Irvin's suspension and Greg Scruggs's injury, Carroll would tryout Tony McDaniel or even the LB's (K.J. Wright would make a decent LEO) on the line if he needs to.

To conclude, let's look at the play of all four positions when they are rotated out of starters to review what the position responsibilities are and just how each component - the LEO, the 1-Tech, the 3-Tech and the 5-Tech - work together to stop the offense. The play below, while results in a 6 yard gain by Frank Gore, shows just why it is so important for everybody to do their job correctly:

































(Big thanks to Danny for creating the gifs!)

Need to catch up? Do so here:

Defining the Seahawks' Defense: An Introduction - Field Gulls

Defining the Seahawks' Defense: Pete Carroll's Journey - Field Gulls

Defining the Seahawks' Defense: The Defensive Line, Part 1 - The Interior Duo - Field Gulls