A chop block is a high-low or low-high combination block by any two players against an opponent (not the ball carrier) anywhere on the field, with or without a delay between blocks; the “low” component is at the opponent’s thigh or below. (A.R. 9-1-10-I-IV). It is not a foul if the blockers’ opponent initiates the contact. (A.R. 9-1-10-V)