Light Box

A light box is six or fewer defenders within five yards of the line of scrimmage and inside the tackle box. For an offense in 11 personnel, a six-man box gives the offense a numbers advantage in the run game — five blockers plus the back accounts for all six fitters, and any extra hat can spring a chunk run.

Light box looks come from two-high coverages. With both safeties in the deep half, the defense only has seven defenders to work with at the second level, and the apex on each side has coverage rules that pull him out of the box. Modern run schemes (inside zone, outside zone, gap pulls) all eat light boxes when the offensive line wins on its blocks.

The defense's bet against light box runs is that the offense can't sustain. A six-man box concedes 4-5 yards per carry but takes away the explosives. The trade is intentional — defenses would rather give up four yards on the ground than 40 in the air.