In white-knuckle final race, 6-year-old mare Zenyatta missed out on becoming the first female horse to win the Breeders’ Cup and retiring undefeated — literally, by a nose. Zenyatta raced in 19 races before the 2010 Breeders’ Cup and won all of them. Not even Secretariat, a Triple Crown winner who won the Belmont Stakes by a still-standing record 31 lengths, was undefeated.
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