An emery ball is an illegal pitch in baseball, in which the ball has been altered by scuffing it with a rough surface, such as an emery board or sandpaper. This technique alters the spin of the ball,

In baseball, a pitch is the throwing of a baseball from the pitcher to a batter at home plate. The term comes from the Knickerbocker Rules. Originally, the ball had to be thrown underhand, much like p