A few years back the Oklahoma Sooners decided to make a major transition on their defense and embraced the 3-4 front after years of playing the 4-3 Under Bob Stoops. There was a lot of sense behind the move at the time, they had a unique hybrid in Eric Striker that they wanted to get into space and a DL coach in Jerry Montgomery that excelled at teaching 3-4 D-line technique.

Neither of those components remain in 2017, although the Sooners have found another impressive space-backer in former 5-star recruit Caleb Kelly. With Lincoln Riley taking over as head coach, long-time 4-3 practitioner Mike Stoops remaining at DC, and fellow 4-3 practitioner Ruffin McNeil joining the staff as DT coach it made sense to move back to the old 4-3 front. Likewise so did the Sooners’ repeated struggles to land top DTs in recruiting due to the unsexy nature of the 4-0-4 defensive front they were utilizing:

The design of this 4-0-4 front (two 4i-technique DEs and then a 0-tech nose tackle) is to clog up the interior B-gaps with the DEs, let the nose clog an A-gap, and then have the linebackers run to the football.

This worked out fairly well for the Sooners in 2014 and 2015. In year one in this scheme DEs Chuka Ndulue and Charles Tapper combined for 11 tackles for loss and 5.5 sacks while in 2015 Tapper and Charles Walker combined for 20 tackles for loss and 13 sacks. Then in 2016 those players moved on (Tapper graduated and went pro, Walker had an injury and left the team to focus on the draft) and replacement DEs Neville Gallimore and D.J. Ward combined for just 5 tackles for loss and two sacks.

Not only did the Sooners fail to get much impact from their DL but the linebackers were often lost trying to manage their responsibilities in the 3-4 defense, particularly against West Virginia’s spread run game after senior middle linebacker Jordan Evans went down with injury.

So heading into 2017 after a disappointing season on defense and a few disappointing years of recruiting the DL, the Sooners are pivoting back to what has worked for them in the past.

Mike Stoops’ 4-3 Under front

The Stoops’ brothers rose to prominence in the 1990s and 2000s teaching an aggressive 4-3 Under defense that could smash I-formation offenses with weak side linebackers and safeties that were freed up to fly to the football.

That scheme has faced the need for major adjustment in the spread era but its modern form could give the Sooners a way to make the most of having a pair of ultra-talented 3-4 outside linebackers. Here’s the version of 4-3 Under the Sooners ran in their spring game (the fact that it was just a spring game is duly noted):

The sam linebacker (Caleb Kelly) is lined up out in space and he’s reading the OL for a run or pass read. On a pass he’s helping bracket the slot receiver, on a run he’s attacking the line of scrimmage.

The boundary looks like a normal Under front with the will linebacker playing behind a 3-technique and the jack linebacker (Obo Okoronkwo) playing as a stand-up weak side defensive end. This is a pretty standard Under front defensive look but a different offensive formation reveals the modern tweak:

Aligning a 3-technique defensive tackle to the strong side with a stand-up 9-technique linebacker outside of him is normally defined as an “Over front.” The key here is not the strength of the formation, but where the ball is on the field. OU’s Under front in the spring game didn’t set the strength based on where the TE was but where the field and boundary were in relation to the hash mark.

The nose, strong side end, mike linebacker, and sam linebacker always stayed to the wider side of the field while the 3-technique tackle, will linebacker, and jack linebacker always stayed to the shorter side (boundary). That allows the Sooners to always keep their hybrid-backer Caleb Kelly out in space and pass-rushing Obo Okoronkwo aligned tight on the boundary as a de-facto DE.

The 4-3 Under vs Big 12 spread offenses

The Sooners won’t just sit in this same look all the time next year. They’ll have some blitzes and alternative fronts to mix in to counter specific opponents and prevent their weak spots from being targeted too often. However, the name of the game today in the Big 12 is having a steady base defense that you can always count on to give you a sound plan for everything an offense might do.

If a defense doesn’t have command of a sound base scheme that suits its personnel, the stress of Big 12 offensive spacing and tempo will take it apart.

The major weaknesses of this 4-3 Under comes from what they gave up when they decided to stop clogging either B-gap with a sturdy DE...the horizontal stress that opponents can put on their linebackers. Against a four-receiver spread set like what West Virginia used to torch the Sooners in the run game last year, the offense can choose which linebacker they want to try and overstress. If they want to get after the middle linebacker, they’ll go 3x1:

On a standard zone play with a bubble screen attached to the 3x1 side the middle linebacker (redshirt freshman Jon-Michael Terry) is put in a bind trying to navigate his responsibility to fill the B-gap on a cutback with the need to stop the screen to the #3 slot receiver “H.”

Essentially, the nose needs to command a double team, the strong side end ideally squeezes that gap, and the sam linebacker needs to be very physical in containing that perimeter screen so the middle linebacker doesn’t have to run too far to chase down the ball if the QB tosses it wide.

If the offense wants to put some stress on the will linebacker they can take advantage of him having A-gap responsibility and force him to balance that with covering a slot receiver on the boundary:

This diagram doesn’t really do justice the amount of space that exists between a quick throw on the boundary and the A-gap that the RB could be charging through downhill. However, there’s not a lot of time to handle either the quick dart throw or the downhill run and again, the will linebacker is depending on that 3-tech causing a lot of problems in front of him so he can sit back and then run down the ball after surveying the scene.

You can see the issue at play in this spring game snap:

It’s not a 2x2 set but the offense adds their H-back to the boundary after the snap to create a new gap for the defense to handle. The jack linebacker spills the H-back’s block, which means that the weak side linebacker’s two duties on this play are first to secure the A-gap on a downhill run and then secondly to chase a spilled ballcarrier out on the perimeter. Mostly likely the Sooners would prefer that their weak side DE/LB box the ball INSIDE to the will here rather than spilling it.

But even if so, this play reveals the knife edge that defenses find themselves on against Big 12 spread offenses if they aren’t all on the same page and someone that needs protection is instead exposed.

The easiest solution would be to play more man coverage and keep the linebacker in the box, but against these four receiver sets that would put Caleb Kelly in man coverage on a slot and someone even less skilled in coverage if they wanted to use him to blitz.

This new scheme will allow the Sooner DL to be much more disruptive, particularly the 3-technique who can now wreak havoc on the boundary, and the strong side end who will have a better angle in the pass-rush. It should also keep Okoronkwo and Kelly in position to make good on their unique talents. Finally, the inside linebackers will now have a consistent picture from snap to snap. However, the DL will need to prove worthy of this new scheme and the OLBs exceptional or else opposing offenses will pick the Sooners apart for playing traditional 4-3 personnel.

The Sooners are switching back to a scheme that will be appealing to the types of 3-technique defensive tackles they have been missing in recruiting. In the meantime, they need what they have recruited along the DL to shine in that role or else they’ll be showing off another broken defense. Neville Gallimore is a major key here and a breakout performance by him in 2017 could be just the thing to revitalize both the Oklahoma defense and their DT recruiting.