Mr. and Mrs. Jerry Moss' Zenyatta, undefeated in 13 career starts, was installed as the 5-2 favorite when she takes on males for the first time in the Nov. 7 Breeders' Cup Classic.

She is attempting to be the first female to the win the World Championship's marquee event.

A field of 13, including Kentucky Derby winner Mine That Bird and Belmont Stakes winner Summer Bird, was entered in the $5-million, 1 1/4-mile Classic.

Trained by John Shirreffs, Zenyatta has been dominant throughout her career, with her 2008 undefeated seven-race win streak capped by a victory in the Breeders' Cup Ladies and a championship crown. This year, the daughter of Street Cry has won all four starts. She has earned $2,774,580