Press Association The son of Montjeu kicked off his Classic campaign with a last-gasp victory at Newmarket before running out a hugely impressive winner of the Epsom Derby, but after following up in the Irish Derby he could not quite claim the Triple Crown as he was denied by Encke in the St Leger at Doncaster. A disappointing run in the Prix de l’Arc de Triomphe followed, after which he suffered a severe bout of colic, and although he was brought back for a much anticipated four-year-old campaign, he has looked a shadow of his former self. He turned in a workmanlike victory on his return, but was beaten by Al Kazeem in the Tattersalls Gold Cup and finished fourth behind the same opponent in the Prince Of Wales’s Stakes at Royal Ascot. While a tilt at the Coral-Eclipse at Sandown on July 6 will be considered, O’Brien is unsure whether to persevere with a horse who remains of significant value to his connections as a potential stallion. The trainer said: “He’s a very important horse to us and he’s not one we want to take any risks with. “The last day at Royal Ascot, he obviously hadn’t come back to his best and while the Eclipse is still an option, retirement is something we might have to consider as well. “The spark was never there after his run in the Irish Derby last year. He had a tough race there on testing ground and then had that problem over the winter.” Aidan O’Brien has revealed last year’s 2000 Guineas and dual Derby hero Camelot could be retired after failing to recapture his best form this season.