46 defense

The 46 defense is an American football defensive formation, an eight men in the box defense, with six players along the line of scrimmage (4 playing line technique, 2 in a linebacker technique). There are two players at linebacker depth playing linebacker technique, and then three defensive backs. The 46 defense was originally developed and popularized with the Chicago Bears by their defensive coordinator Buddy Ryan, who later became head coach of the Philadelphia Eagles and Arizona Cardinals.

Unlike most defensive formations that take their names from the number of defensive linemen and linebackers on the field (i.e. the 4–3 defense has 4 linemen and 3 linebackers), the name "46" originally came from the jersey number of Doug Plank, who was a starting strong safety for the Bears when Ryan developed the defense, a role typically played in the formation as a surrogate linebacker.

To stop a passing game, you can't stop it unless you put pressure on it. Now some people are good enough to put it on with a three-man rush; well, we're not. In fact, I don't know whether we're good enough to put it on with a four-man rush. If we have to send eight, we'll send eight, but we're not going to let you sit back there and pick us apart.

I had to use every bit of knowledge and experience and wisdom I had to come up with game plans to attack this defense. It's really the most singular innovation in defensive football in the last twenty years.

The 46 defense was an innovative defense with a unique defensive front, designed to confuse and put pressure on the opposing offense, especially their quarterback. Compared to a 4-3 base defense, the 46 dramatically shifts the defensive line to the weak side (the opposite end from the offense's tight end), with both guards and the center "covered" by the left defensive end and both defensive tackles. This front forced offenses to immediately account for the defenders lined up directly in front of them, making it considerably harder to execute blocking assignments such as pulling, trapping and pass protection in general. Moreover, the weak side defensive end would be aligned one to two yards outside the left offensive tackle, leaving the opposing tackle man-on-man when trying to block the pass rush.

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