NEW YORK (Reuters) - American Serena Williams won the first set of the U.S. Open women's final against world number one Victoria Azarenka of Belarus 6-2 on Sunday on Arthur Ashe Stadium court.

The fourth-seeded Williams, seeking her fourth U.S. Open crown and 15th grand slam singles title, seized the initiative by breaking the top seed in the second game for a 2-0 lead.

Reigning Wimbledon and Olympic champion Williams led 0-40 in the game but Azarenka raised her game to fend off the American, who finally scored the service break on her fifth break point when the Australian Open winner sent a backhand long.

Williams, showing off her power and precision from both sides, registered 16 winners against two for Azarenka, ending the 34-minute opening set with a booming backhand crosscourt winner for another service break.

(Reporting by Larry Fine, Editing by Julian Linden)