when did it start?
1984.
Breeders' Cup Classic
The first running of the Breeders' Cup Classic in 1984 produced an exciting finish between 30–1 longshot Wild Again on the inside, Gate Dancer on the outside and favorite Slew o' Gold in between. 
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.
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Breeders' Cup Classic [SEP] 1980s
The first running of the Breeders' Cup Classic in 1984 produced an exciting finish between 30–1 longshot Wild Again on the inside, Gate Dancer on the outside and favorite Slew o' Gold in between. The three battled down the stretch with Wild Again shifting his path away from the rail and Gate Dancer "lugging in" towards the rail, squeezing out Slew O' Gold. Wild Again finished a neck in front of Gate Dancer with Slew o' Gold less than a length behind. After a 10-minute stewards' inquiry, Wild Again was left in first place but Gate Dancer was disqualified to third.