Riseball
From Wikipedia, the free encyclopedia
A Dimple (Riseball) is a pitch thrown by a pitcher in fastpitch softball. Upon release by the pitcher, the ball has backspin. The backspin on the ball combined with arm and leg lift causes the ball to rise as it moves towards the batter. Jennie Finch is famous for striking out major league ball players with this pitch. The riseball is in effect upside down to a curve ball thrown overhand.
Some baseball pitchers throw a variation of the riseball known as a "backspin fastball." Over the 46 foot distance from the pitcher to the batter in Little League baseball, a baseball thrown horizontally at a speed of 50 miles per hour would be expected to drop about 48 inches. If sufficient backspin is put on the ball by the pitcher, the amount of drop over the same distance is reduced by about 12 inches.
The direction and strength of the wind potentially affects the result of the pitch. The back rotation of the ball creates an air pocket that facilitates the rising action, if the ball is thrown into th wind the air pocket is magnified and the ball rises sharper and the pitcher can throw it lower.
