Australia's Sam Stosur has upset three-time champion Serena Williams of the United States 6-2 6-3 to win the US Open women's final.
Stosur captured her maiden grand slam title to become the first Australian women to win the US Open since Margaret Court in 1973. The last Australian woman to win any grand slam was Evonne Goolagong-Cawley at Wimbledon in 1980.
Williams was bidding for a fourth US Open crown but failed to reproduce her best after sailing to the final without dropping a set.
Throughout the second set she repeatedly argued with the chair umpire, while Stosur remained a model of composure.
The 27-year-old put Williams under pressure from the start with returns that pinned Williams behind the baseline and attacked her backhand, forcing her to make errors.
Stosur broke Williams's serve twice in the first set then three times in the second and only lost her own serve once.
Better known as a doubles player, the ninth seed emerged as Australia's best prospect in years when she made the final at the French Open last year but lost to Italy's Francesca Schiavone.