In what would be the last year for racing at Morris Park Racecourse, in 1904 Tanya became the first filly to win the National Stallion Stakes during the time it was open to horses of either sex. Tanya went on to become just the second filly to ever win the Belmont Stakes, an American Classic that would eventually be the third leg of the U.S. Triple Crown series. It would be thirty-four years until another filly was victorious in the National Stallion Stakes when New York City restaurateur Henry Lustig's Donita M won the 1938 race. Five years later Henry Lustig would own the third filly to capture the race when in 1943 his Mrs. Ames defeated the gelding Stir Up owned by the powerful Greentree Stable. Sonny Whitney's Enfilade in 1945 was the last filly to win the National Stallion Stakes before the separate division was created.
The 1908 passage of the Hart-Agnew anti-betting legislation by the New York Legislature under RepublicanGovernorCharles Evans Hughes threatened the survival of horse racing in the state. In spite of strong opposition by prominent owners such as August Belmont Jr. and Harry Payne Whitney, reform legislators were not happy when they learned that betting was still going on at racetracks between individuals and they had further restrictive legislation passed by the New York Legislature in 1910. The Agnew-Perkins Law, a series of four bills and recorded as the Executive Liability Act, made it possible for racetrack owners and members of its board of directors to be fined and imprisoned if anyone was found betting, even privately, anywhere on their premises. After a 1911 amendment to the law that would limit the liability of owners and directors was defeated in the Legislature, every racetrack in New York State shut down Owners, whose horses of racing age had nowhere to go, began sending them, their trainers and their jockeys to race in England, France and other countries in Europe. Many horses ended their racing careers there and a number remained to become an important part of the European horse breeding industry. Thoroughbred Times reported that more than 1,500 American horses were sent overseas between 1908 and 1913 and of them at least 24 were either past, present, or future Champions. A February 21, 1913 ruling by the New York Supreme Court, Appellate Divisionsaw horse racing return in 1913. However, the number of quality stallions in the United States had diminished to such an extent that it would take several years to get back to normal. The National Stallion Stakes would not be run again until 1926.
