As football evolves and teams employ new passing schemes, defenses are getting more complex. Passers aim to get rid of the ball quickly to many possible targets, NFL secondary defenses are often left scrambling. As a result, it has become more effective for the defense to attack the quarterback.
Most defenses deploy one of two common defensive schemes: the 4–3 and 3–4. In this article, we’ll introduce you to them and see how the NFL odds are impacted both.
4–3 Pass Rush Defense
The two most common 4–3 pass rush defense are the “over” and “under” fronts. Both traditionally played with a “one gap” philosophy – each lineman is responsible for one running gap or rushing lane. In the 4–3 over, the strength of the defensive line is placed against the strong side of the offense. In the 4–3 under, the strength of the defensive line is placed against the weak side of the offense.
For the 4–3 over, the key is defensive tackles’ size. The offensive line is limited in its ability to double-team without risking the defensive ends splitting free. The ideal right 4–3 defensive end is just big enough to play the run but also explosive enough to pass rush. This player comes from the quarterback’s blind side.
For the 4–3 under, there is a heavy burden on the weak-side linebacker. That’s who is required to stop the run behind the pass-rushing right defensive end as well as cover a large zone in front of the deep dropping middle linebacker. The strength of the 4–3 pass rush defensive in either the over or under schemes allows the defense to place seven men into coverage. The key for them is to get pressure with the front four so the rest of the defense can cover.
However, on the flip side, the 4–3 rush defensive end is often seen as a premium position in the NFL. That’s due to the requirement of the player to possess the rare combination of size, skill, and speed. In a perfect world, they produce double-digit sacks without allowing double-digit yards from the offense’s run game.
3–4 Pass Rush Defense
In the traditional 3–4 pass rush defense, the nose tackle is responsible for covering both A gaps. Ideally, the nose tackle is a 320 pound plus space-eater who is capable of taking on a double-team. At the same time, they can still stop a running back. Additionally, 3–4 defensive ends must be complete two-way players, usually 280 pounds or more. While their main responsibility is to stop the opposing team’s running game, they must also get to the quarterback. That means they have be able to beat offensive tackles.
The biggest threat that the 3–4 pass rush defense poses to offenses is the two interior linebackers. With the abilities to not only assist in picking up coverage slack from the left side by blitzing the outside or in combination with the outside, they are also able to execute one of the most difficult-to-stop blitzes in football – the Double A Gap Blitz – which often results in quarterback sacks.
While the 3–4 pass rush defense has its fair share of advantages, there are also some disadvantages to this defensive scheme.
The most well-known disadvantage of the 3–4 pass rush defense is its requirement for “natural” nose tackles. A classic example is Vince Wilfork of the New England Patriots during their dynast. Natural nose tackles are a dime a dozen due to the fact that nose tackles must be able to overpower tackles and tight ends in the running game. However, they also possess the speed and technique to sack the quarterback.
How This Impacts Betting
If you’re examining what style of defense a team plays and what quality, it typically impacts over-unders. That’s because if it’s a good defense, the game is likely to be a grind-it-out, slow-paced type of game. If they’re bad, we’re likely looking at a high-scoring affair.
It’s important to see not only what style of defense is being played but how good the unit is – one way or another. That has the biggest impact on whether the game will go over or under.