Weird play

[Indy_Ref]

I was discussing a situation the other day with some fellow referees when this question came up: What do you call if a ball goes up through the goal and comes back down through the same goal?

We knew that the goal couldn't count, but weren't sure if it resulted in an alternating possession situation or a violation. Two 6-year guys looked through the rule book and the case book while I officiated and couldn't find the ruling. Does anyone know? I've looked myself, but haven't found anything yet.