Palm ball is exactly what the name might suggest.
The ball is held severely back in the palm and is choked a great deal. This position
of having the ball back in your palm and your fingers basically wrapped around the ball
causes the ball to lose its velocity and works much like a change up in its actions and the
fact that it looks like a fast ball, it acts like a fast ball but it is several miles per
hour slower than the fast ball. That’s what makes it an effective pitch. It is used basically
in the same situations as a change up would be used where you are trying to deceive the
batter by changing speeds and that is a palm ball.