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“Mazzone’s snag concept is one of the best in the game at achieving such consistency. The concept is simple, hard to defend, and easy for the quarterback to read.
Essentially, the snag puts the outside linebacker in conflict (as spread offenses so often do), forcing him to either defend the snag route (a route run at a 45 degree towards the middle of the field by the outside receiver, who stops at five yards and looks for the ball) or the swing route by the running back. The number two receiver (second man from the outside) runs a vertical route (usually a corner), which is difficult for the safety to defend if the cornerback gets involved on either the snag or the swing route. The middle linebacker, who (in many defenses) opens towards the number three receiver (the running back), has a long way to run to get involved with the play, especially if it is run to the wide side of the field. The play is not only effective because the quarterback is given easy passing targets, but because forcing the linebackers to vacate the box so often helps the Bruins to establish their prolific run game.”