Every offseason, defensive coordinators around the NFL promise that their defense will be more aggressive and look to get more sacks and turnovers. But rarely do they actually change their schemes drastically to do so. One of Jay Gruden’s biggest challenges when he took the Redskins job was improving a below-par defense. Instead of hiring someone new, he stuck by Jim Haslett, who he had worked with previously.

The Redskins, you may recall, blamed their defensive woes on Mike Shanahan for interfering too much. Gruden will allow Haslett much more control. The Redskins’ defense will continue to use a 3-4 base front, but will look to utilize more 1-gap principles than the 2-gap principles that are typically associated with 3-4 defenses. How much will actually change remains to be seen.

Above is a traditional 2-gap 3-4 front. Nose tackle Barry Cofield is lined up directly over the center and is responsible for the A gaps on either side. The two defensive ends, in this case Stephen Bowen and Kedric Golston, line up over the tackles, or slightly shaded inside. They are playing as 5-technique defensive ends that have to cover the gaps on either side of their respective tackle. The outside linebackers are asked to play contain on the tight end’s side (Ryan Kerrigan in the picture above) and have to cover the cutback if they are on the weak side of the play, as Brian Orakpo is above.

With every gap covered by the defensive line and outside linebackers, the inside linebackers are able to read and react to the play, filling in where they see fit. But as both guards are left uncovered, the inside linebackers are left vulnerable to being blocked by guards who reach them on the second level.

The advantage to this scheme is that the defense can cover more gaps with fewer players, making it more difficult for the offense to run the ball. However, defenders in this scheme have to be strict and patient. They have to wait and read the direction of the play before they commit to their actions. That extra second needed to read and react slows down the pass rush, making it easier for the offensive line in pass protection.

Both Haslett and Gruden have talked about letting the pass rushers loose, which can be difficult to do in a 2-gap scheme. There are a few variants of the 3-4 defense that use 1-gap principles, which would allow Washington to be more aggressive on the defensive line. The Redskins have used plenty of these in the past too.

Above is a 3-4 Under scheme. Wade Phillips, father of Redskins tight ends coach Wes Phillips, used this scheme in Dallas and as defensive coordinator of the Texans. It’s a 1-gap scheme that allows the defense to be much more aggressive from the snap. Each defender is assigned one gap and can attack that gap straight from the snap without as much reading and reacting.

In this scheme, the nose tackle takes an outside shade towards the strong side of the play and attacks the A gap to his side. The strong side defensive end (Bowen in the picture above), plays almost as a 4-3 defensive end, lining up outside the tackle and covers the C gap. That leaves the Mike (middle) linebacker to fill in the B gap between Cofield and Bowen.

On the weak side of the play, the defense gets one-on-one matchups. The right tackle is left on an island against Kerrigan. The defensive end (Golston) lines up as a 3-technique, traditionally a pass-rushing defensive tackle in the 4-3. This is a role that Washington’s big free agent acquisition, Jason Hatcher, found much of his success in last season. The 3-technique is also something I can see Chris Baker being very successful at.

In theory, this scheme suits Washington’s personnel and allows them to put Hatcher in the position in which he dominated against the NFC East last season. However, the Redskins might prefer to stick to the 2-gap principles to help them stop the run. That isn’t to say they would waste Hatcher’s talents. NFL defenses lined up in nickel sub-packages up to 60% of their snaps last year. This is where Haslett will get his opportunity to prove himself to Redskins fans. With the additions of Hatcher and draft pick Trent Murphy to add to Orakpo, Kerrigan, Cofield, Baker and Bowen, Haslett has plenty of talent to work with in those nickel packages. He’ll have to prove that Shanahan really did hold back the defense.

Mark Bullock is The Insider’s Outsider, sharing his impressions of the Redskins without the benefit of access to the team.

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