The Tony Pike-trained 3yr-old barely received a mention in the lead-up to the 1600m group 1 feature as stablemate Kali and favourite Travelling Light captured headlines.
Loire began the race as a $28 underdog after running second-last behind Travelling Light in her previous start in the Soliloqy Stakes at Ellerslie.
Her poor performance was later put down to the filly suffering a heart fibrillation.
On Saturday, it was Loire who made hearts flutter when she overcame a slow start and produced a powerful finish.
"Ellerslie was a real mystery as her two runs at Hawke's Bay over 1200m, a distance too short for her, were very very good," Pike said.
"We always thought this was the race but when you have those heart problems ... they can be one-offs which we hoped was the case when the tests came back all clear.
"She had worked super coming into the race so we rolled the dice. She is a very good filly who is only going to get better as she gets up over further ground."
Rider Michael McNab had to quickly come up with a new game plan after Loire's slow beginning.
Pike praised the jockey for the way he worked the filly into the clear after she became awkwardly placed at the rear before the home turn.
"It was a super ride by Michael off a slow tempo," Pike said.
"We had talked about trying to be a bit closer as we thought there wouldn't be much speed in the race.
"She got shuffled back but he didn't panic and he has ridden her superbly.
"He rode her at Hawke's Bay and has always liked her."
Loire's win gave group 1 rewards to owners Brent and Cherry Taylor, of North Island breeding farm Trelawney Stud, after they decided not to part with the filly.
The 3yr-old was to be part of the large annual draft the couple send to the Karaka yearling sales until they withdrew her from the catalogue.
"We had actually been [wondering] about whether to put her in the sale all along," Brent Taylor said.
"We kept thinking why you would offer up such a well-bred Redoute's Choice filly and then go and try and buy one from someone else.
"She then got a small niggle with one of her hooves which confirmed what we had been thinking so we decided to keep her and race her ourselves."
The Taylors race the filly with close friend Kate Plaw, also of Cambridge.
Loire scored by a long neck over runner-up Jennifer Eccles in a close finish. Favourite Travelling Light was three-quarters of a length further back in third.
Second favourite Kali disappointed when battling into sixth.
The Pike-trained 3yr-old raced at the rear of the field with the winner before the home turn.
Kali peaked on her run in the straight, while Loire powered to the line.
