Barend Vorster controlled the pace on the Tony McEvoy-trained Westport and the Not A Single Doubt filly did the rest, safely holding the challenge of Indiscretion to open her stakes account in Saturday's Listed Oaklands Plate (14000m) at Morphettville.
Keeping up a strong gallop, Westport defeated Sebring filly Indiscretion by one and a quarter lengths with a further four and a quarter lengths back to Hinchinbrook filly Pouting Lips.
Since making her debut when unplaced in the Group III Blue Diamond Preview at Caulfield back in January, Westport has reeled off three consecutive wins.
"I think when we digest this race that this win will be much better than it appears," McEvoy said.
"She jumped a bit better today but Barend is on a $1.60 favourite and he thought I am not going to let them cross me.
"They actually went too fast, they went very hard and she had to sustain it and she set it up for Phillip's (Stokes) filly (Indiscretion), but she was still good enough to win.
"She's a star of the future. I just wanted to see her today at the 1400m, we've got that, and we also have got a Group 1 race in Sydney worth a million dollars called the Golden Rose.
"We will sit down with the owners, have a nice glass of red and decide what to do."
A $220,000 purchase by McEvoy Mitchell Racing out of the Torryburn Stud draft at the 2018 Magic Millions Gold Coast Yearling Sale, Westport (pictured as a yearling) is the second foal of the Shamardal mare Sister Bruce who was purchased by Torryburn for just $20,000 at the 2014 Patinack Farm dispersal.
A second in a Sunshine Coast maiden was her best result in seven starts. A half-sister to the stakes-placed Un de Sceaux (Hinchinbrook), Sister Bruce is a granddaughter of the Group II SAJC Sires Produce Stakes winner Tristabelle whose daughter Racy Belle is the dam of the Champion 2YO in Australia in 2004, the 2yo Triple Crown winner Dance Hero.
Sister Bruce has a weanling colt by Press Statement and a weanling colt by Astern.
She was covered by Pariah last spring.
Westport becomes the 66th stakes-winner for Not A Single Doubt who will stand at Arrowfield Stud in 2019 at a fee of $110,000.