did the racehorse get defeated ever?
Yes, at the  Travers Stakes at Saratoga Race Course.
American Pharoah
Three weeks later, he finished a close second in a hard-fought Travers Stakes at Saratoga Race Course on August 29, 2015, snapping a winning streak of eight races.
who won the triple crown before american pharaoh Affirmed. how did it get the name? : American Pharoah's name is inspired by that of his sire, the Nile, and his dam's sire, Yankee Gentleman. The horse's name also acknowledges his owner Amhed Zayat's own Egyptian-American background. what is it about? American Pharoah  is an American Thoroughbred racehorse. name a few race events it has participated in? American Triple Crown and the Breeders' Cup Classic. what does the first one refer to? In the United States, the Triple Crown of Thoroughbred Racing, commonly known as the Triple Crown, is a title awarded to a three-year-old Thoroughbred horse who wins the Kentucky Derby, Preakness Stakes, and Belmont Stakes. and the latter? The Breeders' Cup Classic is a Grade I Weight for Age thoroughbred horse race for 3-year-olds and older run at a distance of on dirt. when did it start? 1984. where? It is held annually at a different racetracks of United States as part of the Breeders' Cup World Championships.
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American Pharoah [SEP] Introduction
American Pharoah began his 2015 campaign with wins in the Rebel Stakes and Arkansas Derby and went on to win the 2015 Kentucky Derby and 2015 Preakness Stakes. He won the Triple Crown in a wire-to-wire victory at the 2015 Belmont Stakes, becoming the first American Triple Crown winner since Affirmed in 1978 and the 12th in history. His winning time was the second-fastest for a Triple Crown winner. He next shipped to Monmouth Park and easily won the Haskell Invitational on August 2. Three weeks later, he finished a close second in a hard-fought Travers Stakes at Saratoga Race Course on August 29, 2015, snapping a winning streak of eight races.