I've talked to some wildlife experts about this type of scenario, and usually the only reason a predator will play with it's prey its because it's not hungry. I remember watching my cats play with mice and birds they'd captured alive and brought into the house to play with in the middle of the night.
Once the prey loses it's entertainment value or the predator gets hungry enough, it will be eaten.
But then there are those extraordinary videos we've all seen where natural enemies become best friends ...