John O'Shea has cast doubt over Haussmann's appearance in the Winter Stakes as he weighs up whether to run the horse on what is threatening to be a rain-soaked Rosehill track.

The Godolphin trainer doesn't believe Haussmann handles genuinely heavy ground despite the horse's last-start Civic Stakes win coming on a surface rated in that range.

"He's probably doubtful. I know he won on the heavy the other day but I thought it was a very conservative track rating," O'Shea said.

"When (Godolphin racing manager) Darren (Beadman) walked the track he thought the ground on the rail was just slow, that's why we rode him like we did.

"I don't think Haussmann is overly effective on really heavy ground."

Rosehill was rated a heavy eight on Thursday but with more rain forecast for the back-end of the week, Australian Turf Club racecourse manager Lindsay Murphy is preparing for a further downgrade.

"The way the forecast is, we could be looking at a (heavy) 10 more than anything else," Murphy said.

O'Shea has already scratched Pearls, a full sister to triple Group One winner Helmet, from the Bob Ingham Handicap and says stablemate Inner Circle is an unlikely starter.

Inner Circle has been earmarked for a Golden Rose campaign and Godolphin isn't keen to risk him first-up on a wet track.

However, those conditions won't worry pre-post Winter Stakes favourite Two Blue.

The Kristen Buchanan-trained mare has been relishing Sydney's wet tracks this winter and followed a victory at Rosehill last month with a narrow last-start second to Haussmann in a Civic Stakes result dominated by the on-pace runners.

She is the only obvious leader in Saturday's race and Buchanan says the six-year-old has continued to thrive.

Regular rider Paul King will be back aboard in the Winter Stakes after apprentice Winona Costin deputised for him last start when King had riding commitments in Queensland.

Buchanan has 15 horses in work but has been enjoying great results in Sydney despite her small numbers.

Lucky Liaison won at Warwick Farm on Wednesday and Two Blue is a $4.40 favourite to claim her first black-type victory at Rosehill.

"Things are going really well, I just hope I can keep the momentum going," Buchanan said.

"The horse is well, she's ready to go and I'm happy with the barrier draw."