Hot walker Cesar Zarco helps give Kentucky Derby entrant Union Rags a bath at Churchill Downs on May 2, in Louisville, Ky.

Kentucky Derby entrant Daddy Nose Best grazes after a morning workout at Churchill Downs Wednesday, May 2, in Louisville, Ky.

Exercise rider Zeke Castro takes Kentucky Derby entrant Went the Day Well for a workout at Churchill Downs on May 1.

Horses and exercise riders walk to the track during early morning workouts as preparations are in full swing for the 138th running of the Kentucky Derby at Churchill Downs in Louisville, Kentucky, on May 1.

Horses come around the bend in the Juvenile Fillies Turf race during the 2011 Breeders' Cup World Championship horse races at Churchill Downs in Louisville, Kentucky, November 4. Jockey John Velazquez aboard Stephanie's Kitten rides took first place in the race.

Juan Leyva rides Musical Romance to victory during the Filly & Mare Sprint race at the Breeders' Cup horse races at Churchill Downs Friday, Nov. 4, in Louisville, Ky.

A horse makes its way to the track for a morning workout at Churchill Downs Friday, May 6, 2011, in Louisville, Ky.

Race fans watch horses gallop on the track during early morning workouts at Churchill Downs in Louisville, Kentucky, May 6, 2011.