Caravaggio is "very sore" after his disappointing run in France on Sunday.
Aidan O'Brien is, however, convinced there was an issue with the Scat Daddy colt's footwear when he laboured into sixth place after a slow start in the Prix Maurice de Gheest at Deauville.
He said: "Caravaggio was shod before the July Cup and the day before he was just a little bit footy.
"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.
"It's a bit like a fella running in a sprint with spikes on him and the fella alongside running with slippers on. He's just not getting the traction.
"He is a front-wheel-drive horse – he works from the front. We think there is an issue there and especially when he was so sore."
O'Brien accepts Caravaggio could now be a doubt for the inaugural running of The Everest – the richest turf race in the world – at Randwick in October.
He added: "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 (at the Curragh) over five furlongs (Flying Five Stakes) on Irish Champions Weekend.
"Then he could go on to Ascot."