Chris Waller has the chance to take his season tally of Group One wins to 16 with runners on opposite sides of the world this weekend.

The champion Sydney trainer will saddle up Brazen Beau in the Diamond Jubilee Stakes at Royal Ascot just hours after Catkins chases her first Group One success in the Tattersall's Tiara at the Gold Coast on Saturday.

Waller is Australia's leading Group One trainer this season with 14 elite wins, three of those achieved during the Queensland winter carnival.

Catkins is among the leading chances for the Tattersall's Tiara, the final Group One of the Australian racing season.

The mare has an outstanding record on rain-affected ground and appears certain to get conditions to suit at the Gold Coast where the track has been rated in the heavy range.

Australian bookmakers have Brazen Beau a clear-cut favourite to win at Royal Ascot.

Catkins holds down the third line of Tiara betting behind Najoom and Srikandi.