Is a Rising Pivot Foot in Pitching Illegal?

Question
My daughter is a pitcher. As part of her delivery at times her pivot foot becomes airborne by a small amount...but is not replanted until after her lead foot hits the ground. There is no 2nd contact or push off. The rule books seem to prohibit this..but only as it relates to a crow hop. By definition if the pivot foot becomes airborne is that an illegal pitch or only if it is part of a crow hop?..thanks

Answer
Hi Robert,

What you are describing is a "leap" and that is an illegal pitch.

A leap occurs when both of the pitcher's feet become airborne on the initial move as the pitcher pushes from the pp.  The pivot foot must remain in contact with the ground following push off from the pp.

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