I'm just using the definition of violent conduct, as that is what you would be sending him off for. I don't see that as being even close to violent, it was just a petulant act that had zero chance of hurting the opponent.
Just don't see how you could let play restart when you are about to caution the keeper and everyone can see there are two balls in close proximity. Playing on when a second ball enters the pitch is fine as long as it doesn't get in the way, but allowing play to restart knowing there is another ball on the pitch just can't be done.
