Hybrid Defense: The 4-3 Under

Geoff Burke-USA TODAY Sports

Aiming to take an in-depth look at this hybrid defense we keep hearing about. It will most likely resemble some form of the 43 Under defense elements of which we see with the Seahawks (also look at the Niners and Texans) and which is becoming more prevalent around the league as a whole. This analysis will be of the football-nerd variety, but I'll try to define any terminology I use in case folks who aren't familiar want to get a little nerdier.

The advantages of this defense are simple... gap assignments become the key to success which makes for less need to read offensive formations on a play-to-play basis and the extra meat you gain up front makes defending the run more consistently successful while allowing 1 or 2 specialists to really be the pass rushers.

When taking a long look at what this defense requires of it's players... it's fairly reassuring to discover that the Eagles have a lot of what they need and even have a number of guys who might look better in this defense than they ever did in the previous scheme. That said, there are a couple pretty clear gaps that will leave us crying for upgrades. Obviously, a lot of this will become more clear as we move into camp and through the preseason... but let's a take a preliminary look at where our guys might function in this scheme (You can click on that image to enlarge it).


Now, the defense is awfully versatile as far as the variety of personnel that might appear at any given time and this diagram is really just one version of it. But it's the version I think will be the 'base' for the Eagles.

I am going to talk about the Front Seven almost exclusively, here...

The basic structure is 3 down linemen and a 4th player who can be down or up (this is the LEO). Along with 3 linebackers. So if the LEO is right up at the line of scrimmage, you've technically got a 4-3 alignment, but with 3-4 personnel. Hence... that term... HYBRID.

Here are the ingredients:

LEO or PREDATOR. Perhaps, the most important position on the defense. Or at least the one who's going to have the opportunity to get his name called all day. He's going to be a pass rusher about 94% of the time while simultaneously manning the C-gap (the running lane on the outside of the weakside OT). Based on pure physical stature and characteristics, this feels like the natural role Trent Cole would play in this scheme. Generally we're talking about a smaller defensive-end... quick... natural pass rusher. Based on his performance at the end of last season and his (probably) weak play in coverage... I think Brandon Graham is the best fit here. His measurables, as he continues to lose weight in preparation for the scheme shift, will look a lot like Chris Clemons' in Seattle. The really unique thing here is that this LEO is going to stay on the weakside of the offense all day. This prevents double teams and makes it far less likely that he'll ever have to defend the pass. Because of the single-use purpose of this player, I feel like Graham is a great fit. No one's ever accused him of being a terribly versatile football player, but there's little doubt that he can rush the heck out of passers... he did it all career long at Michigan and did it at a ridiculously impressive clip when he was healthy last year.

WEAKSIDE DEFENSIVE TACKLE. This is, ideally, a guy who's your premiere interior pass-rusher. A 3-tech (this means he will attack in between the guard and tackle on the weakside) specialist who also has the bulk and skill to plug the B gap (between that same guard and tackle) against the run. This is one spot where the Eagles will certainly not have a problem. Fletcher Cox is pretty much built for this role. The only way he's not playing it in 2013 is if the coaches feel like they need him more as a strongside defensive end. Cox has ideal size, measurables, and skillset to be a 3-technique weakside defensive tackle. He and Graham would team well on the weakside.

STRONGSIDE DEFENSIVE TACKLE. This is your space-eater. A big bodied, 1-technique (this means attacking either side of the center) player whose responsibility will be to attract double teams (guard and center) and to plug the strongside A gap (the space between the center and the guard) in the run game. Ideally, you're looking at someone who is over 315 pounds and all-day strong. Folks who were rallying for the Eagles to Draft Jonathan Hankins were imagining him in this spot. Bennie Logan will need to put on a little bit of weight (he could stand to gain 10-15 pounds) but otherwise he's a guy who could excel in this role. His lack of 'stats' at LSU while freeing things up for Mingo and Montgomery speak very well to his ability to play this role. The fact that he earned jersey #18 in the process speaks to the fact that he relishes the role of 'space eater' and doesn't mind not getting the glory. Logan and Isaac Sopoaga, in my opinion, will share this role with Antonio Dixon spotting here and there. We haven't seen Clifton Geathers in action yet... but he's here to audition for depth at this spot, too. Between all of these guys, I think the Eagles look to be okay here. Especially if Logan takes this year by the horns and really develops.

STRONGSIDE DEFENSIVE END. This is the spot where I feel like we're the most empty. Really, Fletcher Cox would be the best player on the roster here. We're talking about a guy who's capable of being a traditional 5-technique (which means attacking the outside of the OT) defensive end, but is also a run-stopping specialist (he'll be responsible for the C gap on the outside of the strongside OT). As far as size goes... you're looking for someone who's hovering around 300 pounds (that size is pretty important because there's no way this player can get blown out of holes in the run game) but is quick enough to do at least minimal damage when asked to rush the passer. This is the spot folks who were hoping for Star Lotuleilei in the Draft were looking to fill. In drafting Joe Kruger and David King, the Eagles were trying to find a guy for this spot, too. Folks who are trying to hold onto what they love and claim that Trent Cole can play this position are mistaken. He just doesn't have the size or strength to be counted on here. Truly, Thornton and Kruger are the best candidates unless Cox slides over to this spot and Thornton takes the weakside DT job. Either way it becomes clear that we may be one lineman short of an ideal front in the 43 Under scheme.

WILL LINEBACKER. This is a candidate for leading tackler. He'll patrol the weakside A gap (between the guard and center) in the run game and be quick enough and athletic enough to cover lots of ground and make plays in the passing game as well. Height isn't a big deal here... he can be short and quick. But he's absolutely got to have speed and the instincts of a middle linebacker. Mychal Kendricks, in my opinion, was built for this role. I think he'll thrive in this defense because his biggest strengths really are exactly what's asked of a WILL in a 43 Under base. He's got the tackling ability to be staunch against the run, but his real bread and butter is lateral movement and pure, unadulterated speed as a linebacker. He's probably just about the fastest LB in the NFL. We're set here.

MIKE LINEBACKER: This is your traditional 'middle linebacker.' He's going to be the field general and the leader of your defense. He'll play with instincts and savvy just as much as he will with talent and he'll have to be equally adept at covering the strongside B gap (between the guard and tackle) as he is at covering the middle 3rd of the field in the short passing game. DeMeco Ryans certainly seems to be the right player for this job. It's a damn hard job in this defense. You're left 'uncovered' against the run which means you'll often have to fight off a guard and you're often left needing to cover (or at least stop) backs and tight ends running short routes over the middle. Ryans has the size at nearly 250 and over 6'. He certainly has the brain/instincts/leadership for it. I know people question his ability to thrive in a 34 defense... but in a 43 Under he'll be a good fit in the middle.

SAM LINEBACKER: If the Dolphins had taken Lane Johnson at #4, this is where we'd plug Dion Jordan into the defense. That did not happen so we're looking at new addition Connor Barwin. Barwin will be on the field. We know that. But whether or not he'll be here is already a pretty hot debate: does he have the coverage skills and is he better used as a passrusher given his productivity in that role in 2011? Truth-be-told... Barwin probably is better used as a pass rusher. The SAM linebacker is responsible for the D gap (outside of the tight end on the strongside) in the run game and is often the guy who's asked to cover that tight end in the passing game. He'll also be asked to rush the passer every now and again. Barwin has the size (6'4'') to cover tight ends, but clearly the Texans felt comfortable letting him go once they had JJ Watt in house to be the main pass rusher. Barwin's best role could actually be as the LEO or PREDATOR if the Eagles find someone else who can be a SAM. Trent Cole sure could make everyone's life easier by showing up to camp and looking like a born SAM linebacker, but I don't see it happening. I think this is Barwin's job to lose and his to keep. This makes me apprehensive because I'd love to see Barwin put in a position where he can rush the passer more often, but I just don't see anyone else on the roster who's going to be formidable in the run game (250-265 pounds probably) and can run with and match up with tight ends (6'4'' with about a 4.6 40-yard dash).

And that' your front 7. There are some names (most notably Vinny Curry) that didn't appear up there. That's because I don't see a really natural fit for them in this scheme. But that's where versatility comes in. Perhaps Curry is a guy that comes in on a particular package... perhaps even Phillip Hunt makes an appearance somewhere. A lot of this will clear up as we move into training camp.

Was this boring? Not to me. I love to take a peek behind the curtain and try to imagine what the Eagles might look like after their first major change in about 15 years. I hope it's interesting to at least some of you out there...

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