Trainer Aidan O'Brien admits Caravaggio is in doubt for a trip to Australia after pulling up sore from his disappointing run in France.

Caravaggio has been one of the favourites for the $10 million Everest in Sydney on October 14 but has now been beaten twice including his sixth in Sunday's Prix Maurice de Gheest at Deauville.

O'Brien said the colt was sore after the race and blamed new footwear.

"Caravaggio was shod before the July Cup and the day before he was just a little bit footy," O'Brien said.

"We changed the style of the shoe that he was wearing to one with a bit of rubber between the foot and the shoe itself. He was 100 per cent when we put them on.

"He just didn't travel the way he can travel, and he ran again in those shoes on Sunday.

"Ryan (Moore) came back in and said he's just not getting any traction.

"The rearing up in the stalls is something we can sort but when he came out Ryan said he's changing and not feeling comfortable.

"He pulled out very sore, so there is obviously an issue with the shoes that he is wearing.

"Obviously it's very hard to say he could go to Australia after his last two runs.

"We will see how he is in a week to 10 days, and if we can get him back to the way we know he can move he could come back here (the Curragh) over five furlongs on Irish Champions Weekend.

"Then he could go on to Ascot."