What it is

The 46 defense is a variation of the 4-3 in which the strong safety moves close to the line, so that six or seven players are near it. It was created by Buddy Ryan.

In a game

The crowded line sends blitzers from many places and overwhelms the offensive line. The defensive backs are left to cover receivers one on one.

More detail

It was famous in the 1980s for its fierce pass rush. The weakness is deep passes, since few players are back in coverage, so modern teams use parts of it rather than the whole.

Animated diagram

1. Six or seven defenders crowd the line of scrimmage, and one safety is close to it.
2. At the snap many of them rush at once, from different directions.
3. The offense cannot block them all, but the receivers are covered one on one.