Today’s NFL offensive landscape is changing rather quickly. The question was asked a few years ago: when will the spread offense or throw-first offense creep into the NFL landscape and grow roots? Well, that time is here. The NFL has turned into a pass-first league and the numbers from the 2011 season prove that.

For the first time in league history, there were two quarterbacks that threw for over 5,000 yards in a season, and the New York Giants’ Eli Manning was 67 yards from completing the trifecta.

Drew Brees, New Orleans Saints: 5,476 yards; 46 touchdowns

Tom Brady, New England Patriots: 5,235 yards; 39 touchdowns

Eli Manning, New York Giants: 4,933 yards; 29 touchdowns

Aaron Rodgers, Green Bay Packers: 4,643 yards, 45 touchdowns (did not play in final game)

When I took a look at the top offenses in the NFL in passing yards per game, it was no surprise that all of them made post-season play, and after the Wild Card weekend, only one has been eliminated thus far in the Detroit Lions.

1. New Orleans Saints: 334.2

2. New England Patriots: 317.8

3. Green Bay Packers: 307.8

4. Detroit Lions: 300.9

5. New York Giants: 295.9

The most popular defense in the NFL was the 4-3. The 3-4 defense went on a major decline in popularity over the years, but recently head coaches have found renewed use of the 3-4 at both the collegiate and professional levels. The only difference in both is the 3-4 has three defensive linemen and four linebackers, while the 4-3 has four defensive linemen and three linebackers.

The key to the migration or popularity back from the old run stuffing 4-3 in the NFL, has to do with the pass-happy NFL offenses today that were run-first in the past. The 3-4 defenses also use different variations like the 2–4–5 (two defensive linemen, four linebackers and five defensive backs) and the 1–5–5 (one defensive linemen, five linebackers and five defensive backs), based on formations used by offenses with four- to five-receiver sets.

Teams that use the 3–4 defense include the San Diego Chargers, Kansas City Chiefs, Dallas Cowboys, New York Jets, Green Bay Packers, Miami Dolphins, Baltimore Ravens, Buffalo Bills, Arizona Cardinals, San Francisco 49ers, Pittsburgh Steelers, Washington Redskins, and Houston Texans.

While all defensive coordinators have the flexibility to incorporate the 52 defense (a version of the 3-4), rushing the passer has become the premium in today’s game. The Ravens and many other teams run a hybrid 3-4 defense and will occasionally shift back and forth between the 4-3 to the 3-4 throughout the game based off scheme.

In 2009, Green Bay made the switch from the 4-3 to the 3-4 defense with the hiring of defensive coordinator Dom Capers, who I worked with at Carolina when he was the head coach of the Panthers. Other teams that have made the transformation to the 3-4 are the Houston Texans under defensive coordinator Wade Phillips, and the Buffalo Bills, both installed in 2010.

The top five ranked defenses in total yards are ranked below. All made post-season play except the New York Jets. There are currently five (Houston, Denver, Baltimore, Green Bay, San Francisco) of the eight remaining teams fighting for the Lombardi Trophy that run the 3-4 defense.

NFL top five defenses (yards allowed per game)

1. Pittsburgh Steelers: 271.8

2. Houston Texans: 285.7

3. Baltimore Ravens: 288.9

4. San Francisco 49ers: 308.1

5. New York Jets: 312.1

In my research. there are two great football minds that are given credit for the 3-4 defense: Joe Collier, who coached the Denver Broncos and is dubbed the godfather of the 3-4 scheme, and Dick LeBeau, who is currently the Steelers’ defensive coordinator. But it depends on who you talk to or which research you believe. Others say it was originally designed by Bud Wilkinson at the University of Oklahoma in the 1940s. Chuck Fairbanks learned the defense from Wilkinson and is credited with importing it to the NFL.

Talking to a former Chicago Bears coach that was on the 1985 Super Team, he mentioned that the Bears have never used the 3–4 defense. When I was with coach Jim Haslett at St. Louis, he was promised the installation of the 3-4, but it never happened with the Rams. After he was hired as defensive coordinator with the Washington Redskins in 2010, he made the switch and runs the 3–4 for the first time in team history.

The Steelers have used the 3-4 as their base since 1982, and were the only NFL team to use the 3-4 defense during the 2001 NFL season, finishing as the league’s No. 1 defense. Because the NFL is a copycat league, the Steelers’ success operating the 3-4 defense with consistent production is the second reason why many NFL teams have started returning to this high pressured defensive formation.

Here is a little history. In 1972, the Miami Dolphins were the first team to win the Super Bowl with the 3–4 defense, going undefeated. The Oakland Raiders defeated the Philadelphia Eagles in Super Bowl XV, the first where both teams ran a base 3-4 defense. How can we forget the 1986 New York Giants, who won Super Bowl XXI with a 3-4 defense that featured arguably the best outside linebacker to play the game in Lawrence Taylor.

When you look at personnel and the defensive linemen used in the two fronts, in the 4-3 they are coached to get out of their stance, with first-step quickness, use of hands to slap, rip and create separation with up-field penetration. This is called the “one-gap player,” and generally they are smaller-framed players. In the 3-4, defensive linemen are coached to step and control offensive linemen with strong use of hands to strike, grab and steer, controlling the line of scrimmage. This is called a “two-gap player.” These linemen are much larger to take up space and allowing linebackers to run and hit.

As an former NFL executive, I can tell you it is much easier to find pass rushers for a 3-4 defense than it is to draft a Julius Peppers (who I helped draft) to play a true defensive end in a 4-3 as a pass rusher and run stopper. Generally, an undersized defensive end in college does not fit the standard 4-3 front in the NFL, but is highly sought after for the 3-4. But again the player’s ability to drop into space with awareness will be a key attribute for the outside linebacker/pass rusher in a 3-4 front.

While the NFL is almost split on which defense they run, no matter the defense the goal on offense remains the same: protect your quarterback and go hurt theirs. With the changing of the guard on offense to a more wide open aerial attack, the key again will be the ability to rush the passer, but also have athletes on the edge at the linebacker position that can drop, change direction and close on both the ball and receivers in space, in order to match up with the high-powered offenses in the NFL.