ARCADIA, Calif. --- Zenyatta had a quiet Friday morning at Santa Anita, one day before she puts her 13-race unbeaten streak on the line against the boys in the $5 million Breeders' Cup Classic.

Zenyatta will bid for immortality as the first filly or mare to win the richest race in North America.

It will be a demanding 11/4-mile test against a deep and talented field that includes Kentucky Derby winner Mine That Bird , Belmont Stakes winner Summer Bird and Rip Van Winkle , a top runner from Ireland.

"She is going to have to have her 'A' game and be lucky, too," exercise rider Steve Willard said after taking the mare for an easy gallop. "The distance will be right down her alley but, there are five or six really good horses in there and no slouches. I just want her to have a safe race, come home good and make babies."

This will likely be Zenyatta's final race. The 5-year-old mare is headed to retirement and a new career as a broodmare.

PAYS TO BE INFORMED: Informed Decision capped a brilliant season with a 11/4-length win in the $1 million Filly & Mare Sprint.

She rarely missed a beat, going 6 for 7 this year. The lone defeat was a third in the Ballerina Stakes run in the slop at Saratoga. Informed Decision has three Grade 1 wins this year, along with the Madison Stakes at Keeneland and Humana Distaff at Churchill Downs.

The 4-year-old is 11 of 14 overall, including 7 for 7 on synthetic tracks.