In baseball, this is a fastball pitch characterized by the index and middle fingers gripping the baseball perpendicular to its seams. The four-seam grip creates a fastball with high velocity and backspin.
In addition to the placement of the index and middle fingers, the thumb should be resting on the smooth surface of the bottom of the ball, directly in the center of the "horseshoe seam". The four-seam fastball is held more loosely than other grips as well, resulting in less friction-which keeps the velocity of the fastball high. Since the ball leaves the thumb first when it is released, it creates backspin that rises, countering the gravity pulling down on the ball, resulting in a uniform, level pitch that relies mostly on speed and position. The four-seam fastball is the most common type of fastball used by pitchers.