New York, United States, 21 August 2013 | tennis.com.au/AFP

World No.13 Sam Stosur, the 2011 US Open champion, has been seeded No.12 for the 2013 edition of the tournament beginning Monday 26 August.

The reason for her elevation comes following the retirement of world No.7 Marion Bartoli, which saw all women ranked below her move up one spot in the seedings list.

World number ones Novak Djokovic and Serena Williams were confirmed on Tuesday as the top seeds.

Spain’s Rafael Nadal, who returned to No.2 in the world this week after winning back-to-back Masters titles at Montreal and Cincinnati, is the second seed with reigning men’s champion Andy Murray seeded third.

Murray will be defending a Grand Slam title for the first time and also trying to win back-to-back majors for the first time after his triumph at Wimbledon.

Roger Federer, a five-time US Open champion, has dropped to seventh, his lowest seeding at Flushing Meadows since 2002.

Djokovic has reached at least the semifinals in each of the last six years, and the last time he was the top seed, in 2011, he took home the crown.

Williams, a 16-time major winner, is the reigning US Open and French Open champion.

She beat reigning Australian Open titlist Victoria Azarenka in last year’s finale in New York, but Azarenka upset Williams in last week’s WTA final in Cincinnati, a battle between the world’s top two.

Williams is followed in the seedings by Azarenka, former top-ranked 2006 US Open champion and 2013 French Open runner-up Maria Sharapova, Agnieszka Radwanska, and Sara Errani.

Two-time champion Venus Williams, currently ranked 60th in the world, is unseeded for the tournament that begins on Monday.