Zenyatta, installed as the early 5-2 favourite, is going against male competition for the first time in her career in the US$5 million Classic. The imposing five-year-old will start from barrier four in the 2,000-metre race with Mike Smith in the irons, after owners Jerry and Ann Moss and trainer John Shirreffs plumped for the Classic rather than attempt a repeat of her 2008 victory in the Ladies' Classic for fillies and mares.

"Optimism is high," Jerry Moss said. "Everybody is in for a treat."

Zenyatta is grabbing the attention in the absence of Rachel Alexandra, who won all eight of her races this year, including three wins over male horses. Owner Jess Jackson shut her down for the season because he dislikes Santa Anita's synthetic track on which his two-time US Horse of the Year, Curlin, faded to fourth in last year's Classic.

No filly or mare has won the Classic in its 25-year history.

Zenyatta goes into the race, the culmination of a two-day, 14-race progamme worth US$25.5 million, with 13 victories in 13 starts.

A raft of European raiders are seeking Breeders' Cup spoils, among them a pair vying to wreck Zenyatta's unbeaten record. Her competition includes Irish import Rip Van Winkle, who arrived off back-to-back triumphs over a mile in the Queen Elizabeth II Stakes at Ascot on September 26 and the Sussex Stakes at Goodwood on July 29.

Henry Cecil, seeking a first Breeders' Cup win of his storied career, saddles Champion Stakes hero Twice Over. "Obviously, the mare has to be respected, she's unbeaten," Cecil said. "I have never seen her, but her career speaks for itself.

"Rip Van Winkle is a very good horse," Cecil added. "If he's on top of his form he'll take a lot of beating."

Cecil said Twice Over would adapt to Santa Anita's Pro-Ride synthetic surface. "He's a horse that went through a stage where he lost his confidence, and he's got that back," Cecil said. "He won the Champion Stakes on ground he didn't really like. He's come out of it very well, and has more chance than the betting tells us."

Zenyatta will face plenty of home-grown competition as well, including Belmont Stakes-hero Summer Bird, long-shot Kentucky Derby-winner Mine That Bird and the Bob Baffert-trained Richard's Kid. Both Rip Van Winkle and Summer Bird will be racing on Pro-Ride for the first time, while Zenyatta has claimed 11 of her 13 wins on the surface.

Associated Press,
Agence France-Presse