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Meet the defense: who's who

The eleven players on defense, where they line up and what each group is there to do.

A defense has eleven players, in three groups that line up in layers: the defensive line up front, the linebackers behind them, and the defensive backs - the secondary - furthest back.

Each layer has a different job. The line fights the blockers. The linebackers are the all-rounders, helping against both the run and the pass. The secondary covers receivers and stops anything that gets past everyone else.

Step through the diagram to meet each group. The defense is in red; the offense is the outlined dots.

A base 4-3 defense against three receivers
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Four linemen on the line of scrimmage: two defensive tackles (DT) inside, two defensive ends (DE) outside. Their job is to beat the blockers - stop the run, and get after the quarterback.

Read the play step by step
  1. The defensive line: Four linemen on the line of scrimmage: two defensive tackles (DT) inside, two defensive ends (DE) outside. Their job is to beat the blockers - stop the run, and get after the quarterback.
  2. The linebackers: Three linebackers a few yards behind them. Left to right: the WILL (weak side), the MIKE (middle) and the SAM (strong side - the tight end's side). They stop the run, cover backs and tight ends, and sometimes blitz.
  3. The secondary: The defensive backs. Cornerbacks (CB) cover the receivers out wide; the free safety (FS) and strong safety (SS) are the deep last line of defense. Notice nobody is across from the slot receiver (H) - that's the job a nickel back is brought in for.

How to spot it

  • On the TV angle, the big players crouched on the line with a hand on the ground are the defensive line.
  • The players standing a few yards behind them, between the linemen and the secondary, are the linebackers.
  • Cornerbacks are out wide, across from the receivers. Safeties are the deepest players, often near the top of the screen before the snap.
  • Count the defensive backs. Four is a base defense, five is nickel, six is dime. The defense swaps them in for linebackers when the offense brings in more receivers.

Key terms

Quick quiz

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Which defenders line up deepest, as the last line of defense?