Just tested on po with a sableye (thanks btw 2 people forfitted which i gained almost 100 points from :D) Ok so heres what happened.
Unfortunally because of sucker punch it coudnt have pranster but i did manage to confuse an opposing gigalith.
I used sucker punch it failed,(Confused) it used stealth rock.
I used sucker punch it failed,(Confused) it hurt itself in confusion
I used sucker punch,(Confused still ;) ) it used rock blast i fainted.