List of US Open Women's Singles Champions - History

History

The women's singles rules have undergone several changes since the first edition. From 1888 through 1911, the event started with a knockout phase, the All-Comers singles, whose winner faced the defending champion in a challenge round. The All-Comers winner was awarded the title by default six times (1893, 1899, 1900, 1905, 1906 and 1907) in the absence of the previous year's champion. The challenge round system was abolished with the 1919 edition. Since 1887, all matches have been played as the best-of-three sets, except in the eleven-year period from 1891 until 1901, when the challenge round was scored the best-of-five-sets. From 1894 until 1901 the women were required to play best-of-five sets in both the all-comers final and the challenge round.

Before 1887, the winner of the next game at five-games–all took the set in every match except the All-Comers final and the challenge round, which was won by the player who had won at least six games and at least two games more than his opponent. This advantage format was introduced for the final sets of early rounds for women starting in 1887, and used for all sets in all rounds from 1887 through 1969. The tie-break system was introduced in 1970 for all sets, in its best-of-nine points sudden death version until 1974, and in its best-of-12 points lingering death version since 1975. The US Open is the only Grand Slam tournament to have a third set tie-break, which has occurred twice in women's singles finals in 1981 and in 1985.

The court surface changed twice, from grass (1887–1974), to Har-Tru clay (1975–1977), to hard courts since 1978. No women's tennis player won the event on all three surfaces, and no women's tennis player won it on both grass and clay. Chris Evert was the only one to win the event on clay and on hard court, thereby making her the only woman to win on two different surfaces at the event.