Football Defensive Line

football defensive line

The defensive line in football is a group of players that line up opposite from the offensive line on the line of scrimmage. These players are responsible for stopping the opposing team’s offense from advancing down the field and scoring points, as well as putting pressure on the quarterback to force sacks. The defensive unit is one of the most important aspects of a football team, and a well-rounded or poor defense can make or break a game for their team.

The different positions on a defensive line include:

The defensive line is responsible for:

  • Countering the offensive line of the opposing team
  • Stopping offensive players from making forward progress
  • Minimizing running lanes for the ball carrier
  • Sacking the quarterback while he has the ball
  • Tackling the ball carrier

Defensive Line Positions and Responsibilities

Each position on the defensive line has the same goal: stop the opposing offense. However, they have different roles in achieving this goal. Read on to learn about the individual positions on the defensive line.

Nose Tackle

football nose tackle

The nose tackle is a lineman in the middle of the defensive line. They stand opposite the center in the offensive line. The nose tackle charges the center player after the snap. Nose tackles are most commonly featured in a 3-4 defensive scheme.

The nose tackle must be careful not to enter the neutral zone before the snap. A penalty called encroachment will be called on the nose tackle.

Defensive Tackle

football defensive tackle

A defensive tackle is one of two linemen in the defensive line that stand opposite the guards of the offensive line. They are responsible for closing gaps and tackling ball carriers on the interior. The two defensive tackle positions in football are:

  • Left Defensive Tackle: Lineman on the left of the nose tackle on the defensive line
  • Right Defensive Tackle: Lineman on the right of the nose tackle on the defensive line

Defensive End

football defensive end

Defensive ends line up at both ends of the defensive line. They stand opposite the offensive tackles. Defensive ends have the best chance to sack the quarterback, as they close the pocket from the outside and force the quarterback to scramble. They are typically faster than defensive tackles.

Defensive Line Schemes

Below are some common formations used by the defensive line:  

4-3 Defense

football 4-3 defense

A 4-3 defense is a scheme with four defensive linemen and three linebackers. The 4-3 features two defensive tackles and two defensive ends on the defensive line. This formation allows for more gaps to be filled and more pressure to be put on the quarterback if passing. The defensive ends will typically rush the outside, while defensive tackles clog the interior.

3-4 Defense

football 3 4 defense

A 3-4 defense is a scheme with three defensive linemen and four linebackers. The 3-4 defense features two defensive ends flanking a nose tackle on the defensive line. The two defensive ends will rush the outside gaps while the nose tackle puts on interior pressure. Linebackers will assist the nose tackle when they see an interior run.

Gaps and Alignments

Defensive coaches use a combination of lettering and numbering systems to describe specific “gaps” between the offensive linemen, as well as how defensive linemen will line up in relation to the offensive linemen across from them.


The A gaps are located in between the center and guards. The B gaps are between the guards and offensive tackles. The C gaps are between the offensive tackle(s) and tight end(s), and the D gap is outside the tight end.


football alignments

For defensive line techniques, even numbers are for “head-up” positions (when the defender lines up directly across from the offensive lineman) starting at 0 across from the center and ascending order to the outside. Odd numbers are for alignments (or “shades”) to the outside shoulder of the offensive player.

There are also inside-shoulder techniques, which use even numbers followed by an “i” designation (because the defender is lining up even with the offensive lineman’s eye).

Gap and technique codes are used to quickly tell players where to line up and where to go when the play begins in a timely manner. For example, in a 4-3 Over defense, the strong-side defensive tackle lines up in a 3-technique and plugs the B-gap. This means they line up on the outside shoulder of the left guard and plugging the gap between the left guard and left tackle.


What is the defensive line in football?

The defensive line is a grouping of players that line up on the line of scrimmage across from the offensive line. The three positions on the defensive line are defensive ends, defensive tackles, and nose tackles. Nose tackles line up directly across from the center. Defensive tackles also line up on the interior, flanking the nose tackle on each side. Defensive ends play on the outside of the defensive line.

What does the defensive line do in football?

The defensive line is responsible for stopping the offense of the opposing team from advancing down the field and putting pressure on the quarterback. The defense attempts to stop running and passing plays made by the offense in various ways, including by sacking the quarterback, blocking or tackling ball carriers, and potentially causing turnovers such as interceptions or fumbles.

How many players are on the defensive line?

The number of players on the defensive line depends on the defensive scheme. In a 3-4 defensive scheme, there are only three defensive linemen: one nose tackle and two defensive ends. In a 4-3 defensive scheme, there are four defensive linemen: two defensive tackles and two defensive ends. There are countless other defensive schemes, but these two are the most common.