The agony of losing the New Zealand Oaks on protest has been all but erased in Sofia Rosa's tough ATC Australian Oaks win.

A week after New Zealand colt Tavago won the ATC Australian Derby, Sofia Rosa dug in for a tough Oaks win at Randwick on Saturday.

The anguish of losing the New Zealand Oaks in the stewards' room was countered with the filly's win in the $1 million race.

"It's a brilliant experience to come here on a big day like this and deliver," managing owner Lib Petagna said.

"Particularly after the disappointment of the New Zealand Oaks."

Trainer Stephen Marsh was worried Sofia Rosa's bad habits might cost her as she entered the straight in the Australian version.

"She still wanted to do everything wrong in the straight, I thought 'oh here we go again'," Marsh said.

"But she was good to the line and it's just a huge buzz to win a race like this."

Winning jockey Hugh Bowman rates her as one of the most difficult horses he's ever ridden.

"She's got some manners - they're all bad," Bowman said.

"You don't mind when they've got that ability."

Sofia Rosa will now return to New Zealand for a spell, but Marsh believes she is the type of horse which could be strong in a Caulfield Cup.

Marsh said she has a lot of development left, likening her three-year-old body to a two-year-old's.

"She's very hard work," Marsh said.

"But you don't mind when they've got that ability."

The $65,000 filly earned close to $900,000 in holding off Ambience and Believe.

Petagna named Sofia Rosa after his great niece, while his other star female Lucia Valentina is named after his daughter.

"The family names are proving pretty lucky for me," Petagna said.