A sinker pitch, also known as a two-seam fastball, drops just before it hits the plate, confusing the hitter. It drops farther than a normal fastball, but has almost the same speed and is therefore a great weapon in the repertoire of a skilled thrower. You will need to hold the ball with your fingers parallel to the seams, with your thumb directly under the ball. Practice throwing the sinker with slightly different finger positions to find the grip that allows you to perform the best throwing motion.
Steps
Step 1. Put your fingers along the seams
Turn the ball so that your index and middle seams are long when they are closest. The fingers should be placed directly over the seams, parallel. Fold back ring and little fingers.
Try an alternate grip. Instead of putting your fingers on the seams where they sound closest, move your fingers higher and place them over the horseshoe. This position is slightly more comfortable for some pitchers
Step 2. Fold your thumb under the ball
The thumb will have to grip the ball from the opposite side, where there are no seams. You should hold the ball steady with the side of your thumb so it doesn't slip out of your hand.
Step 3. Squeeze the ball
Your fingertips should be slightly inside the seams, against the smooth part of the ball immediately next to them, for a firmer grip. The thumb should be pinched against the bottom of the ball, pushing against the fingers.
Step 4. Release the ball
Your middle finger should be pointing directly at the batter when you release the ball. During the final part of the movement, the thumb will push slightly towards the whole. This release is the same as that of the four-stitch fastball, and the opposite of that of a curveball.
Step 5. Practice being more in control
It is more difficult to control a sinker than a four-stitch fastball. Releasing from a two-seam grip gives the ball more rotation than it otherwise would. The grip is also slightly less tight than that of a traditional fastball.
For this reason, it is important to practice the sinker until you understand all the nuances of throwing before using it in the game
Step 6. Understand what the hitter sees
A sinker is easy to follow with the eyes because it looks like a perfect two-seam toss as it progresses towards the platter. Unlike a curveball, it's not hard to keep your eyes on the ball, and hitters often manage to touch the sinkers. However, since the pitch drops slightly, batters often send the ball to the ground instead of getting solid contact.
