When a pitcher is in a set position, what must they avoid doing to not commit a balk?

To avoid committing a balk while in the set position, a pitcher must not separate their hands before the pitch. In baseball, when the pitcher is in the set position, their hands must remain together until they deliver the pitch. If the pitcher separates their hands while in this position, it can be deemed a violation as it may appear that they are making a motion to deliver the ball or attempt a pick-off throw without actually doing so. This creates a situation that can mislead baserunners and disrupt the flow of the game, which is why such actions must be strictly regulated.

Other aspects of the pitching motion, such as bringing hands together too quickly or pausing after becoming set, can indicate variations in the delivery, but they are not direct violations leading to a balk like the act of separating hands would be. The position of the pivot foot, while critical in maintaining balance and controlling the pitch, does not directly influence the balk rule in the same manner as separating the hands.