AIDAN O’Brien is wary about the prospect of soft ground at Epsom next Saturday for Investec Derby favourite Australia.

The Galileo colt has been all the rage for the premier Classic since his close-up third in the 2000 Guineas at Newmarket on May 3.

However, Australia has not yet been tested in demanding conditions, with his trainer hoping the recent wet spell quickly recedes.

O’Brien said: “We wouldn’t like the ground to be soft.

“He’s a beautiful moving horse, everybody saw the class he showed at Newmarket.

“Obviously soft ground wouldn’t be ideal, but we’ll have to wait and see and hope it’s not.”

O’Brien confirmed at the ‘Breakfast with the Stars’ morning at the Surrey venue yesterday that Australia may be accompanied by Geoffrey Chaucer, Kingfisher and Orchestra.

Joseph O’Brien, the trainer’s son, is set to partner Australia, while Ryan Moore, who won the Irish 1,000 Guineas last weekend aboard the stable’s Marvellous, is poised to get the leg-up on Geoffrey Chaucer.

The latter has this week been well backed in the Derby market after rumours circulated of the colt having beaten Australia in a gallop at Ballydoyle.

O’Brien said: “I don’t know where these (rumours) come from. They have obviously always been on different work regimes and both had different races last time.

“I don’t know where it came from. I didn’t see it if it was, maybe it happened, but I didn’t see it.”

Frankie Dettori admitted at Epsom that he was on the lookout for a ride in the Derby.

When asked if he would consider the Italian, O’Brien said: “It would be very hard to get any better than Frankie. Everyone knows how good he is.”

Connections of Arod warned that the improving colt will not run in the Derby if the ground went soft.