THE English 2000 Guineas, English Derby and Irish Derby winner failed to bounce back from his English St Leger defeat 22 days previously and could only manage to finish a well-beaten seventh under Frankie Dettori.
Dettori's booking was one of the most talked about and discussed jockey bookings since the very same rider was booked for the very same owners (Coolmore) seven years ago, and as the debate over his future with Godolphin continues, Camelot is set for a long winter break.
O'Brien said after the race: "He could be something unbelievable next year," when revealing that the Montjeu colt would remain in training as a four-year-old, rather than head straight to stud where he looks an obvious replacement for his sire who died prematurely this year.
"It was very sporting of the lads to let him run, but he wants fast ground and Joseph (O'Brien) always said that. It's been a long hard season and he's something for us to look forward to next season."
O'Brien remains in the hunt for a second winner in the world's richest race run on turf, as his other hope St Nicholas Abbey also suffered from the testing conditions and now heads back to America for the Breeders' Cup in which he triumphed last year.
Dettori echoed the sentiments of O'Brien as he added: "It was just a long season (which) took its toll. I had a perfect trip and he took me beautifully into the straight on the bridle. But just as soon I knew we were in trouble and in fairness to the horse he's been going for some time since the Guineas."
The race was won by the Irish-bred Solemia, who scored at odds of 33/1 under Oliver Peslier for trainer Carlos Laffon-Parias as the French-trained four-year-old delivered a third gut-wrenching blow to the racing mad nation of Japan as Orfevre was done on the line by a neck.
Tom Hogan produced the only Irish winner on Arc day in Paris as his ever improving Gordon Lord Byron won the Qatar Prix de la Foret cosily in the hands of William Buick.
The four-year-old was supplemented for the race earlier in the week on the advice of Buick who won the race last year and it was a move that paid off.
Gordon Lord Byron began the season finishing 11th of 15 runners in a listed event at Cork, but progressed from that to be placed on all bar one of his 11 runs since and may now head to Hong Kong, according to Hogan.
"He's a very brave horse and was given a fine ride by his jockey," said Hogan who was celebrating his first Group One victory.
"All credit to the owner who has had the guts to stump up €100,000 and some of our friends leased him for the day."
The Cheltenham Festival winning trainer added: "We might take him to Hong Kong for the Mile."