Sidearm is a common way of throwing the ball in the infield, because many throws must be made hurriedly from the glove after fielding ground balls. An infielder's quickest throw to the bases is often from just above ground level, necessitating a horizontal release of the ball.

Is throwing a baseball sidearm bad?

There is a common myth that pitching sidearm or three-quarters to sidearm increases the risk of injury. However, there is no evidence to establish this link. Instead, making pitchers throw over the top can create posture changes that negatively affect performance.

Why do MLB Players throw sidearm?

The sidearm throwing motion is a way to counter balance the weight of the body moving from right to left when a shortstop fields a ground ball up the middle. It is a throwing motion that is fast and can be delivered on the move with much more accuracy than an over-the-shoulder throwing motion.