In the game of baseball, a sinker is thrown by holding the ball on top of the seams and throwing it without elevating the pitch. One of the major keys to throwing the pitch is to stay on top of it.Continue Reading
Place your index and middle finger on top of the ball over the narrow part of the seams. Place your thumb on the complete opposite side of the ball where the seams narrow again on the smooth leather.
Do not rotate your wrist before the pitch is released. Keep the index and middle finger on the top of the ball throughout the release. The pitch does not sink if the hand is on the side of the ball when it is released.
Do not elevate the pitch in the strike zone. There is less sink when the ball is elevated and since the pitch is slower than a normal fastball due to friction, it is more likely to be hit well by the batter. By releasing the ball at a later point and keeping it down, it is more likely to be a weakly hit ground ball.