Boom Brisbane filly My Girl Hayley is no certainty to head south this spring even if she begins her three-year-old season with a win at Doomben.

My Girl Hayley, who was an impressive Sunshine Coast winner at her only start, makes her city debut in Saturday's BOQ Kippa Ring Three-Year-old (1110m).

She has been nominated for the Group One Thousand Guineas at Caulfield on October 10.

Trainer Tony Gollan has a big opinion of My Girl Hayley but he warned about getting ahead of the game by putting too big a wrap on her.

"Saturday will tell us a lot more. She is drawn barrier two, she has a nice weight and the track should suit her," Gollan said.

"But this is a very good three-year-old race so it will give us a much better idea where she is at."

"She has done very well since the first-up run and I would be disappointed if she didn't perform."

He said there had been a lot of merit in My Girl Hayley's win because she had been green in the run.

"Often horses who are green at the Sunshine Coast can get lost up the straight but she responded well and ran handy time for the day," he said.

Gollan said he had no doubts My Girl Hayley would eventually run a strong 1600m.

"But whether we get her out to 1600 metres this campaign is up in the air. She is a Magic Millions eligible filly and there is big money at that carnival in January."

"Anyway she will have to win a few Saturday races before we can be sure she would even make those fields."

Gollan said there were also other races in Melbourne for My Girl Hayley aside from the Thousand Guineas.

The filly is raced by Troy Schmidt's Riverview Syndicate which also owns Traveston Girl.

"My Girl Hayley reminds me of Traveston Girl at the same stage of their careers. But My Girl Hayley has a bit to do yet," he said.