Two-time Grand Slam champion Andy Murray has been seeded third for next week's US Open, while world number one Novak Djokovic takes top spot.
Roger Federer, who moved to second in the world after winning the Cincinnati Open last week, has been seeded second.
Murray took the tournament title in 2012 and is heading to New York in good form having beaten Djokovic to win the Rogers Cup almost a fortnight ago.
Rafael Nadal, who has won the US Open twice in his career so far, has been placed eighth in the seedings at Flushing Meadows, while defending champion Marin Cilic is ninth.
On the women's side, Serena Williams tops the seeds as she bids to claim the first calendar Grand Slam in 27 years following triumphs at the Australian Open, French Open and Wimbledon.
Simona Halep has been seeded second, while 2006 champion Maria Sharapova, who has five Grand Slam titles to her name, is third.
