The Dutch forward gave Arsenal an early lead when he converted Theo Walcott's cross from close range. It was all incredibly easy for Arsene Wenger's side and the two players switched roles at the end of the first-half as van Persie set up Walcott to poke the ball home.
Wayne Bridge was thrown in at the deep end on his Hammers debut and conceded a penalty on 70 minutes when he brought down his tormentor Walcott. Van Persie converted the spot-kick to leave the hosts sinking without trace.
Boos rang around Upton Park at the final whistle from the few fans that remained. Their patience in the Grant regime may have fizzled out but they will surely find some hope if the Martin O'Neill rumours hold any truth.