You can also view previously answered questions in the HSW Question Archive . A successful major league batter gets a hit only 30 percent of the time he comes to bat. One of the ways pitchers lower these chances even further is by throwing a curveball. A curveball is a pitch that appears to be moving straight toward home plate but that is actually moving down and to the right or left by several inches. Obviously, a pitch that curves is going to be harder to hit than a fastball that is moving straight.
Any baseball pitch begins with how the pitcher grips the ball.
To throw a curveball, a pitcher must hold the baseball between his thumb and his index and middle fingers, with the middle finger resting on the baseball seam. When the pitcher comes through his motion to throw the ball, he snaps his wrist downward as he releases the ball, which gives the ball topspin. If the pitcher throws properly, the back of the his hand will be facing the batter at the end of the motion. The spinning action created when the pitcher releases the ball is the secret behind the curveball. This spinning causes air to flow differently over the top of the ball than it does under the ball.