Godolphin might have sent its British-based jockey William Buick to Sydney for The Championships but it was a rival trainer who gave the visitor his first Sydney ride.

Keen for Buick to have a low-key experience before he features for Godolphin, John O'Shea booked him to ride Hexagonal at Randwick on Wednesday.

But when that horse was scratched, Buick was left to make his Sydney debut for premier trainer Chris Waller.

Buick took Navua Mist to the front in the Schweppes Handicap but the horse couldn't sustain the effort and finished sixth to the Gerald Ryan-trained Cartier Rock.

While his first ride wasn't a winner Buick said the experience was invaluable.

"I've got a few more race days over here this time, (including) the Golden Slipper obviously, so it's exciting times," he said.

Godolphin is still finalising its Golden Slipper team but the stable confirmed Buick would be aboard one of its runners in the $3.5 million race.

The champion jockey has ridden in Australia twice before partnering Lost In The Moment for Sheikh Mohammed in the 2011 Melbourne Cup and Gatewood for John Gosden in last year's edition.

He also has an Australian connection through the Paul Messara-trained Ortensia who he rode to win the 2012 Nunthorpe Stakes in England.

Buick will have his first Sydney rides for Godolphin at Rosehill on Saturday when he partners Tarquin and Igraine.

The jockey already has a fan in Waller who said he wouldn't hesitate to snap up Buick's services during The Championships.

"He's very professional. He's obviously a world-class jockey and you don't get to that position for no reason," Waller said.

The leading trainer produced Ballet Suite for a win at Randwick with that filly to be aimed towards the ATC Australian Oaks.

Gai Waterhouse also outlined classic plans for Caped Crusader after he handled a steep distance rise to take out Wednesday's Ranvet Handicap (1800m).

"He's on target for the Derby. He will go to the Tulloch (Stakes) then hopefully the Derby," Waterhouse said.