A check hook is employed to prevent aggressive boxers from lunging in. There are two parts to the check hook. The first part consists of a regular hook. The second, trickier part involves the footwork. As the opponent lunges in, the boxer should throw the hook and pivot on his left foot and swing his right foot 180 degrees around. If executed correctly, the aggressive boxer will lunge in and sail harmlessly past his opponent like a bull missing a matador. This is rarely seen in professional boxing as it requires a great disparity in skill level to execute. Technically speaking it has been said that there is no such thing as a check hook and that it is simply a hook applied to an opponent that has lurched forward and past his opponent who simply hooks him on the way past. Others have argued that the check hook exists but is an illegal punch due to it being a pivot punch which is illegal in the sport.