Fastpitch pitching rule

Question
What are the rules governing the pitcher "displaying" the ball.  My daiughter's
coach has always told her she needs to show the ball in her pitching hand
prior to bringing her hands together and starting her delivery.

In a tournament today, the opposing pitcher was hiding the ball in her glove
when her hands were apart, and she kept the ball hidden throughout the
windup. The umpire said that as long as her hands were apart, she didn't
need to show the ball.

Is there actually a rule about displaying the ball in the pitching hand, or is
this something her coach just wants her to do?

Answer
Hi John,

Here's the ASA rules....
6-1-D. While on the pitcher抯 plate, the pitcher shall take the signal or appear to take a signal with the hands separated. The ball must remain in either the glove or pitching hand.

Good thing you had an umpire that knows the rules....makes for a better game. As you can see the rule clearly states the ball can be either in the glove or the hand.  I don't know if the coach needs more times w/ the rules or if that just their preference although I think it should up to the pitcher and their pitching style.

Mark