Jump to content

1 gap and 2 gap 3-4

- - - - -

This topic has been archived. This means that you cannot reply to this topic.
3 replies to this topic

#1 dawg4life



  • Forum Members
  • PipPip
  • 124 posts

Posted 24 January 2010 - 08:15 AM

2 GAP 3-4-Groh

The 2-gap alignment leaves both offensive guards uncovered by defensive linemen. Instead each ILB covers the “bubble” left by the line. This kind of 3-4 requires a specific class of player. The defensive linemen have to be monsters, able to handle the lineman in front of them and control the gap to either side. Ideally, they’re disruptive enough that the guards have to help in many cases. The inside linebackers need to be big enough to take on a guard on every play if the linemen aren’t good enough to keep them clean.

It’s Parcells’ “Planet Theory” - there are only so many men on the planet big and athletic enough to play defensive lineman in the NFL. To some extent, that theory also applies to the linebackers in a 2-gap 3-4 scheme. Guys like Dat Nguyen won Parcells over, but he wasted no time in looking for guys like Bradie James and Bobby Carpenter and Kevin Burnett to replace smaller players like Dexter Coakley.

Parcells liked the 2-gap 3-4 for a number of different reasons. It’s design makes it more difficult for the offensive linemen to get an angle on his defenders. It makes it easier to drop eight men into coverage and prevent big plays. It makes it easier for a stud OLB to get an angle in pass rush and generate pressure with just four rushers. But it’s also more difficult to play in today’s NFL. Those planet-like defensive linemen are getting harder and harder to find.

1 GAP 3-4-Grantham

The attacking, aggressive style of play of the one gap 3-4 has stood the test of time better than the read-and-react style for much the same reason that the under 4-3 has. It allows players to attack the offense, specifically its ability to disguise the fourth (and fifth or sixth) pass rusher and the coverage behind. In fact, there are a lot of under front concepts in the Phillips 3-4.

Unlike the true 2-gap 3-4, there’s no definite “bubble” in this particular front. The strong side end slides down in the guard-tackle gap and the nose tackle slants to the weak side center-guard gap. The weak side end may or may not be head-up on the tackle, sometimes aligning in a 5-technique. Moving the defensive lineman by just 12 inches changes the philosophy entirely. It’s easy to see how the mindset of the defensive linemen changes. It’s clear that the two inside linebackers can be, if the linemen are disruptive at all, better protected from the blocks of interior linemen. You can see the lines of attack for a delayed ILB blitz or how each OLB might get a jump by shifting one defensive end to the outside of an offensive tackle.

The DL penetrates, and is charged with constant harrasment of the QB. The LBs are typically fast, and at least one of them will blitz on any given play. The reason for the near constant 1-LB blitz is to account for the fact that the outnumbered DL is also relatively undersized and only one-gapping. However, the adjustments work out well. The OL never knows who the blitzer will be, or where he will come from.

The school of thought for the Phillips 3-4 is the need to pressure against the QB to stop the pass threat, and this is done by varying who the "fourth rusher" (who is really a blitzer) is. Add another blitzer in here and there, and the speedy/aggressive Phillips system is a threat to QBs, and attempts to get turnovers by slashing the time that a QB has to make decisions.

#2 Enlightened32


    Starting Lineup

  • Forum Members
  • PipPipPipPip
  • 4,833 posts

Posted 24 January 2010 - 10:06 AM

Dallas led the NFL is sacks in 08, had the 8th best defense in the league this year, and allowed the fewest points in the NFC. Id say this defense works. I cant wait to see it in Athens.

#3 CrimsonKat


    Starting Lineup

  • Pure Football
  • PipPipPipPip
  • 4,589 posts

Posted 24 January 2010 - 11:54 AM

It appears Grantham has adjusted his defenses since working for Saban, but just for informational purposes, Saban runs a split of one-gap and two-gap within the same alignment (which appears to be pretty unique). His system is called the Over/Under 3-4.

We have a 30 side and a 40 side on defense.

The 40 side plays a two technique and includes the Nose and the Strong defensive end. The Nose plays a two technique (we actually call it the 0 technique) and we have a strong defensive end who also plays the two technique. So, for example, you have Cody and a strong-side end, like Lo Washington, who hold blockers. The goal is for them to take up three blockers.

The 30 side on rush down plays the one technique so you would have a weak defensive end (Marcel Dareus) and a jack linebacker (Eryk Anders) who can come up to rush. This is referred to as the Bubble side and a MIKE Linebacker (Rolando McClain) always lines up on this side.

If we are in the Under front, the two technique will be declared by the MIKE to the side with the tight end (or strong side of the offensive front). If we are in the Over front, the two technique will be declared by the MIKE to the side away from the tight end. As offensive personnel shift (i.e., TE in motion across the front), the MIKE shifts the 30 and 40 sides.

Pretty complex system and you have to have a sharp MIKE linebacker (see McClain), but really creates the best of both worlds with containing the run game and placing pressure on the Quarterback.

#4 SacFalcFan


    AFMB Hall of Fame

  • Administrators
  • PipPipPipPipPipPipPip
  • 151,168 posts

Posted 29 January 2010 - 01:31 PM

Crimson you will laugh at this.. mike farrell from rivals said during an interivew yesterday discussing uga and us moving to the 3-4: he said that championships teams in today's college football do not run the 3-4.