The smallest horse in Sydney's premier stable will be aiming for the biggest prize on the first day of The Championships at Randwick.

McCreery is the most favoured of Chris Waller's four runners as he bids to equal the training performances of TJ Smith and Gai Waterhouse with seven wins in Saturday's $3 million Doncaster Mile.

"He is the smallest horse in the stable. He weighs 410 kilos," Waller said.

"Most horses are around 500 kilos and some 600.

"So he is very small. But he is very effective."

McCreery, an $11 chance, has a win and a second on heavy ground which he is likely to encounter on Saturday but was a long way from his illustrious stablemate Winx in the George Ryder Stakes after his win in the Group Three Liverpool City Cup.

He will carry 53kg in the Doncaster with Kerrin McEvoy to ride.

"He's won on wet ground. In the weight-for-age race he had Winx to try and conquer, which he wasn't able to do," McEvoy said.

"But he rode that day as though the track was too heavy for him, which sounds strange for a horse that's already won on heavy ground.

"But he's back to handicap conditions, he's got a light weight on his back, he enjoys Randwick, so he's one of multiple chances in the Doncaster.

"It's a wide open race and he's got to be a chance."

Waller is looking for his fifth consecutive win following Sacred Falls in 2013 and 2014, Kermadec in 2015 and Winx in 2016.

He has also won with Triple Honour in 2008 and Rangirangdoo in 2010.

"The Doncaster is a very special race because it was our first Group One with Triple Honour," Waller said.

"But it's certainly not an easy race to win."

Waller made it look easy in 2014 when Sacred Falls led in an historic first four for the stable beating Royal Descent, Weary and Hawkspur.

His other runners this year are Arod ($71) Endless Drama ($18) and Antonio Giuseppe ($15).

The Kris Lees-trained Le Romain remains the punters' pick at $5.50 to claim his fourth Group One win.

Le Romain has had three starts this preparation for a win in the Group Three Southern Cross Stakes followed by victory over champion sprinter Chautauqua in the Group One Canterbury Stakes.

He goes to the Doncaster after being soundly beaten by Winx in the George Ryder Stakes in which he accounted for third placed Chautauqua by 1-1/4 lengths.