Until Winx arrived, Red Tracer and Catkins were the star mares in the Chris Waller stable.

They came close but neither managed to win Sydney's premier race for fillies and mares, the Coolmore Classic (1500m).

Waller will have four runners in Saturday's edition of the Group One event, including the favourite I Am Serious, all trying to improve on Red Tracer's second in 2013 and Catkins' third the following year.

I Am Serious is raced by respected Taree trainer Bob Haire and his family who sent her to Waller to realise her potential in the city.

She has measured up to top company and won the Group Three Angst Stakes last preparation after two minor placings behind Godolphin's Avilius.

First-up I Am Serious finished a close second to Coolmore rival, the Jason Coyle-trained White Moss, in the Millie Fox Stakes.

"She was brilliant first-up without winning," Waller said.

"She has been set for this race all along and she is a very talented mare. It will be great to be able to get a Group One win for her owner and breeder Mr Bob Haire and family.

"Getting a horse off another trainer to me is a great sign of respect and one that I take very seriously and if we can repay his trust it would be a very special moment.

"That is not to say that it wouldn't be special to win with any of the other mares, having two runners for the Star Thoroughbreds team."

Noire and Fiesta wear the purple and white of Star Thoroughbreds while Waller's other runner is New Zealand Group One winner Savvy Coup.

Formerly trained by Michael and Matthew Pittman, Savvy Coup stayed in Australia after running in Winx's fourth Cox Plate in October.

"Her first-up run was a long way below what I expected so I am hoping that the race will help to bring her on," Waller said.

"Her work seems to be fine but realistically she could still be another run away and obviously she is looking for a little bit further."

Savvy Coup beat just one runner home in the Millie Fox while Noire has been unplaced in two starts this campaign.

Fiesta won the rich Inglis Sprint first-up before a creditable sixth in the Group One Surround Stakes, a little more than two lengths from the winner Nakeeta Jane.

Waller said he was not too concerned about the wet track with more rain predicted overnight ahead of the race day.

"I believe all four of our horses should handle the track conditions tomorrow," he said.

"I walked the track this morning and it has a lovely feel to it. There is plenty of grass which would suggest that we are in for a good three-week carnival at Rosehill."