Every race is a risk for Australia's best horse Winx.

With her winning streak at eight, including five at Group One level, she again puts her incredible record on the line in Saturday's $3 million Doncaster Mile at Randwick.

Trainer Chris Waller admits the pressure is great, but he is thankful the mare's performances do most of the talking.

Winx had her final work-out at Rosehill on Thursday morning, galloping over 1000 metres and breezing up the straight in about 25 seconds.

"Her track work over the last two weeks since racing has been faultless, possibly even the best of her work she's ever shown according to her track riders this week," Waller said.

It's an ominous warning to her rivals from the horse that has changed Sydney's champion trainer's outlook on the sport.

"She's brought about a different perspective of any horse that I've trained," Waller said.

"It's not so much prize money or the status of a race. It's now trying to make sure she keeps winning.

"You can't just keep them in cotton wool and let them run every six months such as a heavyweight world champion boxer. She's got to race every two weeks or three weeks."

While Waller knows Winx is a long way off the global sensation Black Caviar created, the public's interest is building as the Cox Plate winner continues her winning ways.

"She's starting to capture at least the Australian imagination," he said.

And every time she wins the pressure intensifies.

"At the moment it's certainly a new level of pressure for me, but fortunately the horse does the talking and makes my job a bit easier," Waller said.

Saturday's race pits her against stablemate Kermadec, the winner of last year's Doncaster, as well as a group of horses who will have a six kilogram weight advantage.

Kermadec has a three kilogram weight turnaround from his last-start second to Winx in the George Ryder Stakes.

"Although she's giving away a lot of weight to some very good horses my confidence levels are still very high," Waller said.

Waller says Winx is effectively at the halfway point of her racing career and if she can sustain her current dominance for the remainder, it will cement her place among the greats.

"Once she's done that she'll certainly be seen in that elite status of all time."

A win and a speedy recovery from the Doncaster will confirm a start in the $4 million Queen Elizabeth Stakes a week later, one more step on the road to champion status.