On Saturday the country’s best-credentialed miler More Joyous will attempt to add a sixth Group 1 victory to her impressive resume when she lines up favourite in the $2 million Group 1 Doncaster Mile (1600m) at Randwick and trainer Gai Waterhouse is confident that her star mare has what it takes to win.

Four-year-old More Than Ready mare More Joyous is a champion in Waterhouse’s eyes, but her achievements on the track have been overshadowed by those of the world’s best sprinter Black Caviar.

This season alone More Joyous is undefeated in four starts including her smashing last-start win in the Group 1 Queen of the Turf Stakes (1500m) at Rosehill on April 2.

The Queen of the Turf Stakes gave More Joyous her 14^th win from 18 career starts, her fifth Group 1 title and her 10^th consecutive victory in Sydney.

“She’s Australasia’s champion miler,” Waterhouse said.

“She’s the best mile horse we have in Australia, winning the Doncaster sort of crowns this preparation and then it will be off for a spell and she’ll come back for the spring in Melbourne.”

Outstanding form and a flawless record of three wins from three starts over the mile have More Joyous installed as the firm $2.25 favourite in the Doncaster Mile markets.

An added advantage heading into Saturday’s showdown was More Joyous’ ideal barrier eight draw for the Doncaster, however the classy mare was bumped up to the 57kg topweight of the Doncaster field with previous topweight and reigning champion Rangirangdoo a non-acceptor.

While gate eight bought a smile to the face of More Joyous’ jockey Nash Rawiller, part-owner John Singleton is not so sure.

“I’ve got a terrible feeling the winner will be in my mate Gerry Harvey’s blue-and-white colours and her name will be Aloha,” Singleton said.

The Mick Price-trained Encosta De Lago mare Aloha took out the Group 1 Coolmore Classic (1500m) at Rosehill on March 19 before finishing just over a half-length back fourth to Rangirangdoo in the Group 1 George Ryder Stakes (1500m) last start.

On Saturday Aloha is set to start from barrier 11 in the Doncaster and is rated a $9 chance.

“I’d like to say I’m confident but I can’t,” Singleton said.

Waterhouse was far more assured.

“(The Doncaster) is right up her alley,” Waterhouse said.

“She’s very well weighted and she’s got the credentials to do it.”

More Joyous must pull out all the stops on Saturday as she prepares to become the first topweight to score victory in the testing Randwick mile feature since Sunline who carried 58kg to victory in 2002.

A dual Doncaster Mile winner, Sunline was also the last odds-on favourite to win back in 1999.

“Sunline is the best horse I’ve seen and I truly believe over the next two or three years More Joyous can prove herself right up there with her,” Nash Rawiller said.

“It will have to be Sunline-type effort (in the Doncaster) to pull it off with that weight.”

Rawiller has been aboard More Joyous for 13 of her career starts including 11 wins and has nothing but praise for the boom mare.

“She’s a jockey’s dream,” said Rawiller.

“She’s got tactical speed and listens to you in a race and she’s the ideal racehorse going into a very hard-fought, competitive Randwick mile.”

More Joyous showed she was on track for the Doncaster with an impressive gallop at Rosehill on Tuesday morning.

Ridden by Waterhouse’s trackwork jockey Steve O’Halloran, More Joyous completed the 1200m hitout in a blistering 1:22.4, her final 200m run in 11.6.

“She looks as good as she ever has and she’s trained on since the Queen of the Turf,” Rawiller said.

“This (the Doncaster) has been her main aim the whole way through the preparation and she’s obviously right on track to achieve that.

“She’ll be giving some very good horses five and six kilos but she’s got that weight for a reason.

“She’s rarely gone to the races and let us down.”