[potato]

here is their position:

Basket & Board, Offense, Defense.

A1 grabs the rebound, D1 is behind him standing tall & firm arms up to block A1's shooting path, A1 does a pump fake and sticks out his butt and bumps D1, D1 is standing strong but the bump into his tummy or crouch depending on the players high stunned D1, giving A1 a good opportunity to shoot & score. It takes pretty much 1-2 seconds to do such feat.

Have you ever been bumped by the strong pump fake butt bump, it's pretty much like a punch to the tummy but hurt less because the butt surface area is bigger & has more flesh to cushion the impact.

In this case i would say the butt invaded the D1's verticality & made contact with him, however since it's a pump fake it may be incidental? Sometimes case scenario is a good way to explain written rules, that is how they teach law anyway, by using case studies.