Top-seeded Serena Williams won her fifth U.S. Open championship and 17th Grand Slam title overall by beating No. 2 Victoria Azarenka 7-5, 6-7 (6), 6-1 in a windy final. Sunday's match was the toughest test these two weeks for the No. 1-seeded Williams, who also beat Azarenka in three sets in last year's final.