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Decoding Bob Diaco: Nebraska & The 3-4 Over Front

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With the new Nebraska defense on the way, let’s look at another look you’ll see on the field.

NCAA Football: Cincinnati at Connecticut David Butler II-USA TODAY Sports

In the previous article I covered what will be the base front of Bob Diaco’s 3-4 defense here at Nebraska. In this write-up I will introduce one of the many fronts that can be utilized with 3-4 personnel that will already be on the field in the Okie front. The 3-4 Over front is a slight alignment shift from the Okie, where the down defensive linemen (DLM) will shift either half a man or half a gap over and away from the formational strength call; the details of which we’ll delve into later in this write-up.

3-4 Over Front Ryan Reuter

For now, you may be wondering why there would ever be a need for shifting alignments from the base Okie front. The answer is multifaceted, with the nature of an opponent’s running game playing a role in this ideology, how an opponent positions their formational strength to/away from the boundary, and finally, if your defensive personnel is still better suited for the 4-3 Even front spacing with the DLM’s.

In regards to an opponent’s running game, most, if not all, running games can be broken down into two main categories of Zone blocking or Gap/Man blocking. For zone blocking teams, the head-up alignments of the Okie front make it very difficult for the offensive linemen (OLM) to get good blocking angles for solo and combination blocks, in addition to changing the cadence of the covered OLM’s footwork and contact initiation in his blocking progression. Specifically, you will see nose guards create this problem on centers and will drastically alter the ability of the center and play-side guard of climbing up to the second level. Some offensive line’s may choose to simply base block these plays against Okie fronts if they feel that they’ve got better dudes than you’ve got. However, if an opponent is at a decided athletic disadvantage and/or feel that they cannot base block mano y mano, they will switch to a steady diet of gap-blocked plays, with a heavy emphasis on down blocks, angles, double team blocks, and typically a pulling guard.

When the opposing offense goes on an Atkin’s Diet of gap-blocked run plays, the next chess move for the defensive coordinator is to adjust out of the Okie front to an Over or Under front, using the same personnel and same defensive philosophy, with a twist. That twist being how even though 3-4 personnel and philosophy have been the foundational pillars of your defense, the 3-4 Over and Under will use the previously described Even spacing more commonly associated with the 4-3 defenses.

The preeminent adjustments that will occur to morph the Okie front to Over front occurs with a two-way shift between the defensive line and linebackers. Starting with the centerpiece of the 3-4, the War Daddy nose guard who will shift a half-man away from the formational strength call, SAM Left or SAM Right, to align on the backside shoulder of the center; with his strong-side foot splitting the crotch of the center. From this shaded position, the nose guard will still execute his dirty work assignment of eating up blockers in a 2 gap system.

Before we go on too far, I’d like to clarify the formational strength calls. When the offense breaks the huddle and aligns, the MIKE will make a strength call, SAM Left/SAM Right, in accordance to the formation’s numbers and juxtaposition on the field in regards to the field and boundary. Normally defenses will declare their strength to the side the tight end aligns on, however there are exceptions. Some defenses will elect to defend the field should the tight end be aligned to the boundary.

The second alignment change in the morphing to the Over front occurs with the strong-side 5 tech defensive end, who will now reduce down and away from aligning head-up over the offensive tackle to aligning on the outside shoulder of the offensive guard, with the now 3 tech’s backside foot splitting the

crotch of the offensive guard. Typically, the 5 tech who reduces down to serving as a 3 tech DT, will be whichever 5 tech DE maintains better pad level and plays with better leverage in occupying blockers and defending the line of scrimmage. Once the 5 tech has reduced down to aligning as a 3 tech, the Dog linebacker, the SAM in Diaco’s vernacular, will then align on the anywhere from head-up on the TE to being shaded on the outside shoulder of the TE in a 9 tech defensive end role, not to be confused with the Philadelphia Eagle’s ‘Wide 9’ technique. Aligning as the 9 tech DE, the Dog will bring versatility to the positon, as he can still be used in situations of coverage in addition to defending against the run and front-line play. Specifically, and technically speaking, the Dog will be responsible for fitting either into the C gap or D gap on runs toward, while squeezing down the line of scrimmage to account for bootlegs, counters, and cutbacks on runs away.

Away from the formational strength call, the other 5 tech DE will adjust to lining up on the outside shoulder of the offensive tackle, reducing down away from the strength call to play a 6 tech DE. As the Open Side/6 tech DE, the 5 tech turned 6 tech should be the better pass rusher of the two original 5 techs.

The adjustments that take place within the linebacking corps will have the Cat linebacker shifting his pre-snap alignment toward the formational strength call to cancel out any open gaps vacated by the reduction of the defensive line. The Cat will typically account for the weak-side B gap, much like the WILL in a 4-3 defense, essentially rendering the run fits as identical to the actual 4-3.

For the Inside Linebackers, the Mo and the MIKE, the Mo will shift over to align as the 4-3 MIKE. However, this alignment typically will be superficial as the true MIKE will still be acting as the defensive signal caller. Speaking of the MIKE, he will shift over to replicate what the SAM does within a 4-3 defense, cancelling out gaps between the 3 tech DT and 9 tech DE, with his alignment. Within this alignment, many of the coverage responsibilities will be either the TE in man to man coverage or curl/flat responsibilities in zone defense.

Perhaps the single biggest detail that needs to emphasized within the Over front is lining up correctly. This is something that needs to be repped endlessly in practice against the vast array of looks that an offense will throw at the defense. As with any schematic or philosophical shift, there are trade-offs when going from aligning in the Okie to aligning in the Over front. Chief among these trade-offs is the natural symmetry that is inherent in the Okie front, with even numbers of players aligning on either side of the center within the box. The Over front is constantly shifting its alignment in accordance to the offensive formational strength, which presents an increased propensity for an alignment bust and being out-leveraged in defending the run. Formation recognition cannot be overstated enough when aligning in the Over front.

The versatility of the 3-4 defense in terms of personnel and alignment gives Bob Diaco plenty of tools in the tool box to deconstruct an offense’s approach. In the succeeding write-ups, we’ll take a look at the 3-4 Under front, the 3-4 Double Eagle, 3-4 vs Spread, and 3-4 vs Spread Empty.