A brilliant debut stakes-winner at Flemington last spring, the Gai Waterhouse and Adrian Bott trained filly then finished sixth to Houtzen in the Magic Millions 2YO Classic at her only other run last season.
She resumed with a seventh to Houtzen at Moonee Valley in a Group III race last month, but stripped a lot fitter for this 1200 metre assignment.
Drawn wide, Invincible Star (image Grant Courtney) flew out of the gates for Steve Baster to take up the lead and was never headed, powering clear to win by four lengths.
"She's a fabulous filly," said Gai Waterhouse.
"She won the two year-old race here last spring, so it's lovely to see her come back down here and win."
A $200,000 Magic Millions purchase for her trainer from the Yarraman Park draft, Invincible Star runs for a big syndicate of owners including David and Shiralee Lilley in whose colours she runs.
Bred by Yarraman Park, Invincible Star has won two of four starts earning over $195,000 and is the fourth winner from four foals to race from Romany Flyer, a half-sister by former Yarraman Park stalwart Catbird to Group III winner Viking Hero.
The family also includes Group I winners Innocent King, Unworldly and Invest, so Invincible Star is a valuable filly now with two Group wins on the board.