Rachel Alexandra and Zenyatta were the only two horses to receive votes for Horse of the Year in 2009.
Rachel Alexandra, a 3-year-old, won eight times last year, including the Preakness Stakes, the second leg of the Triple Crown, while the 5-year old Zenyatta won all five of her races and was the first female to win the Breeders' Cup Classic.
The award was named for Eclipse, an 18th-century racehorse that started his career unbeaten in his first 18 races, and won 344 times before he finished.
An Eclipse Awards ceremony will be Jan. 18 in Beverly Hills, Calif.
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