Steelers Today - A Pittsburgh Steelers blog

March 22, 2009
By Donald Starver

As the NFL draft approaches, coaches and general managers are busy evaluating potential draftees.  However, players’ college statistics, physical attributes, and combine performances can’t be looked at in a vacuum.  Defensive players in particular, must be evaluated within the context of the specific defensive scheme that the drafting team will utilize.

For example, a particular player may be viewed as too heavy and too slow to play defensive tackle in a 4-3 defense, but might be perfectly suited to play nose tackle in a 3-4 defense.

Before we look at how the Steelers’ 3-4 defense impacts their requirements at each specific position, we first need to define the two key defensive front alignments in the NFL, the 4-3 and the 3-4.

The first number refers to the number of defensive linemen, and the second number refers to the number of linebackers.  So a 4-3 defense would utilize a 4-man front with 3 linebackers behind them.  Contrarily, a 3-4 defense utilizes a 3-man front with 4 linebackers behind them.

In a 4-3 defense, the pass rush is generated by the defensive linemen.  The linemen are tasked with penetrating the offensive line, getting to the ball carrier, or sacking the quarterback.  The defensive ends, in particular, must be able to apply pressure to the quarterback.  Examples of 4-3 defensive ends include the the Houston Texans’ Mario Williams, and the Carolina Panthers’ Julius Peppers.

The linebackers in a 4-3 defense primarily provide run support, and match up against the tight end.  While their role is important, the linebackers in a 4-3 front tend to play a secondary role to the defensive ends and defensive tackles.

In a 3-4 defense, the emphasis is on the linebackers.  The primary role of the defensive linemen is to occupy the blockers to free up the linebackers to make plays.  The pass rush in a 3-4 defense is generated by the outside linebackers.  Examples of 3-4 outside linebackers include the Steelers’ LaMarr Woodley and James Harrison, and the Dallas Cowboys’ DeMarcus Ware.

While there are exceptions to this rule, in general, the defensive linemen in a 3-4 are bigger than the defensive linemen in a 4-3.  This is because each defensive lineman in a 3-4 should ideally be able to occupy more than one offensive lineman.

The outside linebackers in a 3-4 are also bigger than the OLBs in a 4-3.  This is necessary to allow them to take on offensive tackles. Many 3-4 OLBs were defensive ends in college.

The NFL is a copycat league, so many teams are moving to a 3-4 front due to the success of teams like the Steelers, New England Patriots, Baltimore Ravens, and San Diego Chargers.  However, neither system is inherently “better”.  They are just different.

I often hear fans say, “I wish the Steelers would switch to a 4-3″.  This makes no sense to me.  As I mentioned earlier, neither system is better than the other.  There are plenty of teams that do quite well using a 4-3 defense.  The key is the team’s personnel.  If a team tries to implement a 3-4 defense without a dominant nose tackle, they are destined to fail.  Similarly, a 4-3 team that doesn’t have DE’s who can pressure the quarterback will not have much success.

The Steelers’ current roster lends itself to the 3-4.  They don’t have the personnel to run a 4-3 consistently.  In particular, they lack the defensive ends to provide pressure off the edge that the 4-3 requires.  They’d also need to draft a different type of tackle than Casey Hampton and Chris Hoke in order to run a 4-3 consistently.

The Steelers’ famous “Steel Curtain” defense was a 4-3 defensive front.  In fact, the Steelers played a 4-3 until 1983, the season after L.C. Greenwood and Mean Joe Greene retired.

The Steelers have used the 3-4 as their base since that time.  At one point in the mid-90′s, the Steelers were the only NFL team still utilizing a 3-4 defense.  This made it easy for them to get the “tweeners” that typically are converted to linebackers in a 3-4 system, and the oversized nose tackles the 3-4 demands.  However, with many more teams now playing the 3-4, the competition for college talent is much more intense.

Even within the 3-4 alignment, there are many different ways to execute the defense.  There are two primary versions of the 3-4 in the NFL.  The first has its origins with Bill Parcells and the New York Giants.  Parcells utilized Hall-of-Fame outside linebacker Lawrence Taylor in his 3-4 system, and led his Giants to the Super Bowl championship in 1986.  One of Parcells’ assistant coaches was Bill Belichick, who took Parcells’ system to New England.  Belichick disciples Romeo Crennel and Eric Mangini spread his system to other NFL teams.

The second version of the 3-4 was developed by the Pittsburgh Steelers.  While the Steelers have used a 3-4 front since 1983, the current version was really developed in 1992 by Bill Cowher and his assistants, Dom Capers and Dick LeBeau.  Dick LeBeau has tweaked the system significantly since that time, but his system’s origins are clear.

The primary difference between the two systems is where the front 3 line up.  The Parcells-Belichick system is a two gap system which requires their front 3 to line up directly in front of an offensive lineman and control the gap on both sides of that offensive lineman.  Since they have to control 2 gaps, that system is referred to as a “two-gap” system.  The Steelers version is primarily a “one-gap” system.  The Steelers’ linemen play slightly to the side of their blockers, rather than directly in front of them.  They are responsible for controlling only one gap, while the linebacker behind them is responsible for the other gap.

“With the guys we have right now, when you play two-gap you tie them down”, said Steelers’ defensive line coach John Mitchell.  “Aaron Smith can run.  Brett Keisel can run.  Casey does a good job running.  We have good inside linebackers who can cover ground.  We can get away with a line playing one gap”.

Because of the differences in how they execute the 3-4, the Steelers and Patriots will look for slightly different characteristics in their draftees, even though both teams play a 3-4 defense.

In the upcoming installments of this series, we will look at each position within the Steelers’ 3-4 defense to see how that position is utilized, and who the Steelers might consider to fill that role.  First up, in Part 2 of this series is the most important position on any 3-4 defense; the nose tackle.

To read the other installments in this series, click below:

Part 1

Part 2

Part 3

Part 4

Part 5

(If you enjoyed this article, please consider leaving a comment below. Also, please subscribe to our blog by pressing the orange button below. Thanks.)

Subscribe in a reader