Gai Waterhouse is counting on Equator bringing the most improvement into the Spring Champion Stakes as the stable tries to post its first Group One win of the Sydney carnival at Randwick at Saturday.

Tulloch Lodge's usual dominance of carnival racing has been missing from the spring as rival trainer Chris Waller captured two Group One races, Guelph delivered for Peter Snowden last Saturday and Seville for Victorian-based owner Lloyd Williams.

But the stable is growing in confidence that three-year-old Equator will be close to the form which helped him to a Group One placing in the autumn.

Off the scene for 35 days after resuming over an unsuitable distance in the Run To The Rose, Equator held down the minor placing behind Rock Hero and Waterhouse-trained stablemate Liberty's Choice in the Dulcify Quality at Randwick last week.

While a decision to reschedule the Spring Champion Stakes has been questioned by some trainers, it has provided Waterhouse with the lifeline she has needed to get Equator to the race.

"He had a little bit of a hiccup and the mile (of the Dulcify) second-up with the five weeks between runs probably just told in the last bit," stable spokesman Mark Newnham said.

"But now going into Saturday he should be cherry ripe."

Equator's potential was on show during the Sydney autumn carnival when he ran a close third to Guelph in the Group One Champagne Stakes at Randwick.

Despite bookmakers having Equator at $11, it's a formline Newnham expects to help the gelding's chances.

"He's a nice big relaxed horse who got a mile as a two-year-old and he has always shown 1600 metres to 2000 metres will be his best trip," Newnham said.

Blake Shinn will ride Equator while French jockey Thomas Huet will ride Liberty's Choice.

Waterhouse has won the Spring Champion Stakes three times, the latest when Jim Cassidy was aboard Platinum Scissors in 2002.

Cassidy takes over from James McDonald on the early favourite, the John O'Shea-trained Savvy Nature ($3.50) on Saturday, as he bids to ride his 100th Group One winner.

Savvy Nature sustained a long run when second to Complacent in the Gloaming Stakes, suggesting he will be even better served by the extra 200m of the Spring Champion.

Complacent had barrier one in the Gloaming and has the rails draw again but while the gate is the same he too will have a different jockey as Christian Reith replaces Kerrin McEvoy, Darley's No.1 rider who is needed for Caulfield Guineas day mounts in Melbourne.