London - World number ones Serena Williams, aiming to complete the first calendar-year grand slam in 27 years, and Novak Djokovic have been named the top seeds for the US Open starting on Monday in New York.
Williams, winner of the last three US women's singles crowns at Flushing Meadows, is followed on the seeding list by No 2 Simona Halep of Romania, a 2014 French Open finalist.
Russia's Maria Sharapova, the 2006 US Open winner, is seeded third with 2014 US Open finalist Caroline Wozniacki of Denmark seeded fourth.
Five-time US Open champion Roger Federer is the second seed for the men's event where the Top 10 seeds feature five US Open champions and six grand slam winners in all.
In addition to 2011 champion Djokovic of Serbia and Switzerland's Federer (2004-08), former US champions include Andy Murray (2012), Rafael Nadal (2010, 13) and last year's winner, Marin Cilic of Croatia.
Scotland's Murray is seeded third, Spaniard Nadal is eighth and Cilic seeded ninth.
Kei Nishikori of Japan, runner-up last year to Cilic, is seeded fourth, one spot ahead of reigning French Open champion Stan Wawrinka of Switzerland.
Other prominent women's seeds include fifth-seeded Czech Petra Kvitova, the 2011 and 2014 Wimbledon champion, followed at No 6 by compatriot Lucie Safarova, this year's French Open finalist.
Victoria Azarenka of Belarus, a US Open finalist in 2012 and 2013, is seeded 20th. Two-time US winner Venus Williams is seeded 23rd, 2011 champion Samantha Stosur of Australia is 22nd and 2004 US Open champion Svetlana Kuznetsova of Russia is seeded 30th.
A victory for Serena Williams would make her the fourth woman to sweep all four slams in a single season, joining Maureen Connolly (1953), Margaret Court (1970) and Steffi Graf (1988).
It would also be the American's seventh US Open singles crown, breaking her tie atop the all-time list with Chris Evert, and move her into a tie for second on the career grand slam singles list with Graf at 22, two behind Court.
The singles draws for the 2015 US Open will be made at the National Tennis Centre on Thursday.
Seedings for the men's and women's singles tournaments at the US
Open starting on Monday, as announced on Tuesday:
1 Novak Djokovic (Serbia) 2 Roger Federer
(Switzerland) 3 Andy Murray (Scotland) 4 Kei Nishikori (Japan) 5 Stan
Wawrinka (Switzerland) 6 Tomas Berdych (Czech Republic) 7 David Ferrer
(Spain) 8 Rafael Nadal (Spain) 9 Marin Cilic (Croatia) 10 Milos Raonic
(Canada) 11 Gilles Simon (France) 12 Richard Gasquet (France) 13 John
Isner (U.S.) 14 David Goffin (Belgium) 15 Kevin Anderson (South Africa)
16 Gael Monfils (France) 17 Grigor Dimitrov (Bulgaria) 18 Feliciano
Lopez (Spain) 19 Jo-Wilfried Tsonga (France) 20 Dominic Thiem (Austria)
21 Ivo Karlovic (Croatia) 22 Viktor Troicki (Serbia) 23 Roberto Bautista
Agut (Spain) 24 Bernard Tomic (Australia) 25 Andreas Seppi (Italy) 26
Tommy Robredo (Spain) 27 Jeremy Chardy (France) 28 Jack Sock (U.S.) 29
Philipp Kohlschreiber (Germany) 30 Thomaz Bellucci (Brazil) 31 Guillermo
Garcia-Lopez (Spain) 32 Fabio Fognini (Italy)
1 Serena Williams (U.S.) 2 Simona Halep (Romania) 3
Maria Sharapova (Russia) 4 Caroline Wozniacki (Denmark) 5 Petra Kvitova
(Czech Republic) 6 Lucie Safarova (Czech Republic) 7 Ana Ivanovic
(Serbia) 8 Karolina Pliskova (Czech Republic) 9 Garbine Muguruza (Spain)
10 Carla Suarez Navarro (Spain) 11 Angelique Kerber (Germany) 12
Belinda Bencic (Switzerland) 13 Ekaterina Makarova (Russia) 14 Timea
Bacsinszky (Switzerland) 15 Agnieszka Radwanska (Poland) 16 Sara Errani
(Italy) 17 Elina Svitolina (Ukraine) 18 Andrea Petkovic (Germany) 19
Madison Keys (U.S.) 20 Victoria Azarenka (Belarus) 21 Jelena Jankovic
(Serbia) 22 Samantha Stosur (Australia) 23 Venus Williams (U.S.) 24
Sabine Lisicki (Germany) 25 Eugenie Bouchard (Canada) 26 Flavia Pennetta
(Italy) 27 Alize Cornet (France) 28 Irina-Camelia Begu (Romania) 29
Sloane Stephens (U.S.) 30 Svetlana Kuznetsova (Russia) 31 Anastasia
Pavlyuchenkova (Russia) 32 Anna Karolina Schmiedlova (Slovakia)