War Admiral, the offspring of the great Man o’ War, was the best horse on the East Coast in 1937, capturing the Triple Crown in dominant fashion. In the third race, the Belmont Stakes, he injured himself when bolting from the starting gate so powerfully that his hind legs overtook his forelegs, clipping his right hoof with a shoe and gouging out a chunk of flesh. His jockey was unaware of it until he dismounted after War Admiral had won the race and saw blood splattered on the horse’s underbelly. The owner was Samuel Riddle, a cantankerous man who also owned Man o’ War. 

Seabiscuit entered this environment a virtual unknown, but he soon made his presence felt. On June 26, he won the Brooklyn Handicap, in a rematch with Rosemont. Seabiscuit handily overtook Rosemont, but another strong horse, Aneroid, challenged him down the homestretch, drawing even. Neither horse could put the other away, but at the last second Seabiscuit nudged ahead and won by a nose. The West Coast press declared him the best horse in America, but praise from the East Coast was grudging: He would have to beat War Admiral to earn that distinction. 

After two more wins, Seabiscuit raced at Suffolk Downs in Boston.