Zone blitz

The zone blitz is one type of "blitz" (i.e., a common method of sudden and intense defensive attack, in American football). It has near-limitless permutations, all sharing a common theme: intentionally confusing the offensive line by having defenders who were initially positioned to rush (blitz) the passer unexpectedly retreat into covering the receivers instead, while simultaneously having one or more defenders who were positioned to "cover" the receivers before gameplay rush the passer-by surprise after play commences. As this deception is timed to only reveal itself the split-second after gameplay commences, the offense is left no time to properly react and adjust. This results, ideally, in player mismatches that leave one or more openings in the offensive line's pass protection, giving the surprise blitzer(s) a clear and quick path to tackling the passer before he has enough time to attempt throwing the football to an "open" receiver (incurring a sack or even a turnover).

Miami Dolphins defensive coach Bill Arnsparger developed the zone blitz in 1971. He started by placing linebackers on the defensive line and having them drop back into coverage, and eventually included regular defensive linemen as well. The scheme did not gain widespread use in professional football until Dick LeBeau refined it with the Cincinnati Bengals and popularized the zone blitz in the early '90s, while being the defensive coordinator for the Pittsburgh Steelers, earning Pittsburgh the title of "Blitzburgh". Though the zone blitz has become common throughout the NFL, the 3–4 defense—3 defensive linemen, 4 linebackers—lends itself particularly well to this style of play, and LeBeau continues to utilize it today.

The Zone Blitz is usually executed from one of three zone coverage formations.

Cover one is identical to cover zero (where there is no man covering deep into the field, making the coverage mostly man-to-man) with one major exception. One player, typically the weakside or "free" safety is left with no man responsibilities, and can instead roam the intermediate to deep zones.

In cover two, each safety (free and strong) covers a deep half of the field, while the two cornerbacks cover the flats (from the line of scrimmage to about 15 yards deep on each sideline). Three linebackers (weak side, middle, and strong side) drop into coverage, with each patrolling 1/5 of the middle field. A variant of this, the Tampa 2, has been used by the Buccaneers for years and helped them on their way to their only Super Bowl win. This coverage is also the most popular when zone blitzing.

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