Aidan O'Brien has sprung a surprise in announcing his team for the Breeders' Cup World Thoroughbred Championships, with Powerscourt, the Arlington Million (gr. IT) winner, missing his intended assignment in the John Deere Turf (gr. IT), and 3-year-old Oratorio, winner of two prestigious group I races this season in the Coral Eclipse and Irish Champion Stakes, lining up for the Breeders' Cup Classic (gr. I).O'Brien told the Racing Post that Powerscourt "just wasn't right" shortly before confirming his Breeders' Cup entries. "So we decided against entering him". (Powerscourt since has been retired from racing. See Stallion News.) While his absence from the Turf is a blow, the emergence of Oratorio as a Classic contender undoubtedly adds intrigue to the race. Although he never figured in finishing fourth behind 25-1 shocker David Junior in the Emirates Airlines Champion Stakes at Newmarket last Saturday, Oratorio had proved himself a colt of class and resilience in twice coming late to peg back Epsom Derby (Eng-I) winner Motivator – himself a contender for the Turf – in the Eclipse and Irish Champion. O'Brien also intends to run Ad Valorem, sixth to Host in the Shadwell Mile (gr. IT) at Keeneland on October 8, in the NetJets Mile (gr. IT); Ivan Denisovich in the Bessemer Trust Juvenile (gr. I) and Mona Lisa in the Emirates Airline Filly & Mare Turf (gr. IT). That latter plan is significant as it would rule out Kieren Fallon from riding Ouija Board in the same race, thus increasing the prospect of Jerry Bailey taking the ride on Lord Derby's filly, who is quoted a 6-4 chance by British bookmakers. The same race could see Karen's Caper line-up following her encouraging second to Sweet Talker in the Queen Elizabeth II Stakes (gr. IT) at Keeneland on Saturday. Gerard Butler, a former assistant to D Wayne Lukas, priming his Dubai World Cup (UAE-I) fourth Jack Sullivan for the Classic, a race for which Starcraft is easily the main European hope. His trainer Luca Cumani worked the 5-year-old New Zealand-bred son of Nureyev on Southwell's all-weather track Tuesday, after which he said: "That went okay. He would be good enough to win the race on turf; whether he is good enough to win it on dirt remains to be seen."