Pierro's bid to keep his unbeaten record in Sydney intact has gained a further boost with barrier four in Saturday's Doncaster Mile.

The three-year-old is the dominant favourite for the prestigious race over what is regarded as the toughest 1600m course in the country but his owner Greg Kolivos is taking nothing for granted.

"I have a huge amount of respect for (topweight) Shoot Out and the others in the race," Kolivos said.

"A three-year-old carrying 57 kilograms - I'm told it's never been done.

"Pierro could be the one.

"We've stepped the bar this campaign to weight-for-age and we've stepped it up again."

Pierro has won 11 of his 13 starts with his two defeats coming in the Caulfield Guineas and Cox Plate during the Melbourne spring.

The Chris Waller-trained Shoot Out, who finished third behind Pierro and King Mufhasa in the weight-for-age George Ryder Stakes (1500m), will start from gate 10 and is on the third line of betting at $13 with Pierro the $2 favourite in TAB's market which remained unchanged after Tuesday's barrier draw.

Splitting the pair is the Bart Cummings-trained filly Norzita at $8 but she will have to contend with barrier 17.

Stable foreman James Cummings said race tactics would be up to Craig Williams.

"We are very happy to have Craig. He is one of the most analytical jockeys there are and he will study the race," Cummings said.

"James McDonald worked her this morning and he was very, very happy with her."

A field of 20 plus one emergency was declared for the Doncaster with Red Tracer's chances of an elusive Group One win not helped by the outside barrier.

Red Tracer has been runner-up to Appearance at her past two starts in Sydney's two Group One races for fillies and mares - the Coolmore Classic and the Queen Of The Turf Stakes - both over 1500 metres.

She is one of four runners from the Waller stable with veteran Danleigh and three-year-old Sacred Falls completing the quartet.

The Guy Walter-trained Appearance, one of the few Darley top liners from outside the Peter Snowden stable, has been a surprise packet this season after causing an upset in the Myer Classic in the spring.

Darley's Jason Walsh said he was happy with barrier 13.

"It's a nice gate midfield and she should be able to settle midfield," he said.

"She worked this morning with Streama. Kerrin McEvoy rode her and he was pretty happy."

A dual Group One winner at three, Streama began her four-year-old season as the headline act for the Walter stable but she has been upstaged by Appearance and hampered by wide barriers.

That didn't change for the Doncaster and Glen Boss will have his work cut out from 18.

Aeronautical, who produced a career-high third in a photo finish to the Newmarket Handicap, drew barrier one.

Despite heavy rain overnight on Monday, Randwick received just 9mm and was rated in the slow range on Tuesday morning.