Two-seam fastball

A two-seam fastball is a pitch in baseball and a variant of the straight fastball. The pitch has the speed of a fastball and is often referred to as the sinker.

Grip and action

Several different grips are used for a two-seam fastball, the most common of which is to place the index and middle fingers along the seams where they are closest together (where the horseshoes point in towards each other) with the thumb placed directly below on the leather with the rear of the thumb just touching the bottom near seam.[1] The arm action is identical to a four-seam fastball, although the hand action differs slightly. Typically, the two-seam has more movement if the pitcher applies index fingertip pressure, or holds the baseball deeper in the hand.[2] Both techniques cause the ball to spin out of the hand off-center and away from the pitcher, similar to the spin of a changeup.[3]

The two-seam fastball often is perceived to be slower than the four-seam fastball, but the slight pronation of the hand and off-center spin on the ball carries the ball down and toward the pitcher's dominant side, down and to the right for right-handers, and down and to the left for left-handers.[4]

Other Languages
한국어: 투심 속구