Rules to play Baseball
The Set Position
Set Position shall be indicated by the pitcher when he stands facing the batter with his entire pivot foot on, or in front of, and in contact with, and not off the end of the pitchers plate, and his other foot in front of the pitchers plate, holding the ball in both hands in front of his body and coming to a complete stop. From such Set Position he may deliver the ball to the batter, throw to a base or step backward off the pitchers plate with his pivot foot. Before assuming Set Position, the pitcher may elect to make any natural preliminary motion such as that known as the stretch. But if he so elects, he shall come to Set Position before delivering the ball to the batter. After assuming Set Position, any natural motion associated with his delivery of the ball to the batter commits him to the pitch without alteration or interruption.