Ultimate Sniper was expected to find the front in the IRT Pacing Final but after the Barry Purdon trio showed superior gate speed, Ultimate Sniper was left back in the field and had to move to sit parked with a lap to go.
He mastered leader A G's White Socks at the top of the straight and then held out trailer Mach Shard and the booming late finish of Thefixer to complete a faultless series.
All this from a horse who was allowed to miss the New Zealand Cup just a month ago and who the stable had initial fears about how he would handle the Alexandra Park right-handed track.
"He was out on his feet that last 50m but he kept going like the good horses do," said Rasmussen after driving her fifth Inter Dominion final winner, having also trained Blacks A Fake to win four before she joined Mark Purdon in partnership.
Purdon took the reins behind Winterfell in the Trotting Final, and as expert a job as he did, the winning of the race may have been the hands-on training he has done with the former problem child of the open class trotting ranks since he came north for this series three weeks ago.
Winterfell gave punters some nervous moments when he was crossed early, and then when Purdon asked him to work around Majestic Man, he took some fancy steps.
Once balanced up, he got away with an easy lap but copped pressure after from Tough Monarch and then Massive Metro, who headed him at the top of the straight before Winterfell fought back.
Even after all that, he still had to hold out Majestic Man up the passing lane, with the latter throwing away his chance to win by refusing to go down to the passing lane.
But as tonight showed, getting to the All Stars horses is one thing, getting past them is quite another.