A fold block is specific blocking technique where two offensive linemen block two defenders by crossing paths with one another.
Almost always one offensive lineman will have a defender in front of him and an adjacent lineman will not. The lineman with the defender in front of him is said to be covered; the other lineman is uncovered. The uncovered lineman will first block the defender covering the other lineman. The covered lineman will step behind and around the offensive lineman and block a defender further off the ball, usually a linebacker.
A fold block creates advantageous blocking angles for the lineman. The first lineman to block is hitting a defender from the side, which makes his block easier. The second lineman then moves around his teammate to get a better angle on another defender.
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