Not only did the 21-year-old from Heathcote get to steer home a winner for her Rothacker Medal winning father Jim O'Sullivan, but her win aboard Neangar Guy also notched an important milestone.

O'Sullivan's victory in the John Valves Vicbred Pace (1710m) was the 50th in her blossoming young career in the sulky.

"It was pretty special already to get a win on dad's horse, but to get 50 made it even more exciting," she said.

"I've been lucky to have a lot of people supporting me along the way, owners and trainers, who want to put me on their horses.

"I wouldn't be here without them."

It was a return to the scene of one of the most memorable of her 50 career wins for O'Sullivan and with the same horse.

The trainer-driver-horse trio combined to win the last race on the program on Ballarat Cup night back in January.

"It was his first race he won unhobbled on cup night and probably one of my favourite wins," O'Sullvan said.

"He's such a lovely horse, I love driving him. You don't get to drive too many unhobbled horses.

"We had a bit of challenge on our hands from the start. I was wanting to lead with him as he can get a bit lazy.

"But he didn't want to let a horse passed him, which was really good to see."

Neangar Guy, a six-year-old gelding, has now won three of 32-lifetime starts, with nine placings.

He was trained in the early part of his career by Ken Bartels.

Read more: Neangar Guy breaks long win drought

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