The Racing Post reports that the Aga Khan's Sendawar has been retired from racing and that Montjeu has suffered a "training setback" and may miss his scheduled start in Saturday's Irish Champion Stakes (Ire-I).Sendawar (Priolo -- Sendana, by Darshaan), winner of the 1999 Dubai Poule D'Essai des Poulains-French Two Thousand Guineas (Fr-I), was scheduled to defend his title in Sunday's Emirates Prix du Moulin de Longchamp (Fr-I), won by Indian Lodge, but was withdrawn from the race and retired, according to the Post. Sendawar was the highweighted colt at three on the European Free Handicap at distances from seven to nine furlongs and retires with five victories from 10 career starts, earning $745,492. Winless in two starts as a juvenile, Sendawar won four of five starts as a 3-year-old, the only blemish coming in a second-place finish in the Prix Greffulhe (Fr-II) at the hands of Montjeu. Besides the French Two Thousand Guineas, he also won the St. James Palace Stakes (Eng-I) and the Emirates Prix du Moulin de Longchamp (Fr-I). Sendawar won one of three starts of his 4-year-old campaign, that coming in the Prix d'Ispahan (Fr-I) at Longchamp. In his final two starts, he finished fourth to Dubai Millenium in the Prince of Wales Stakes (Eng-I) and placed second in the Prix Jacques Le Marois (Fr-I) at Deauville.Michael Tabor's Montjeu, the likely favorite in Saturday's 1 1/4-mile Irish Champion Stakes, is now uncertain to make the race. "Montjeu is not a certain runner in Ireland," trainer John Hammond told the Post. "He has had a slight training setback and is now only a possible runner next Saturday. We will review the situation in the middle of the week."According to the Post, Giant's Causeway may now substitute for Montjeu in the Irish race and Montjeu may prep for his Prix de l'Arc de Triomphe Lucien Barriere (Fr-I) defense in the Prix Foy (Fr-II).Montjeu has won 10 of 12 career starts, including the King George VI and Queen Elizabeth Diamond Stakes (Eng-I), the Prix de l'Arc de Triomphe Lucien Barriere (Fr-I), and the Budweiser Irish Derby (Ire-I). The 4-year-old son of Sadler's Wells was the highweighted colt at three on the European Free Handicap between 11 to 13 1/2 furlongs.