World number ones Novak Djokovic and Serena Williams were named the top seeds on Thursday for next week's Australian Open with organisers aligning with the current rankings.

Djokovic is chasing his sixth title after beating Andy Murray in last year's final, while Williams, battling a knee injury, is after her seventh Australian crown.

Murray, who has lost in four Australian finals, three of them to Djokovic, is the second seed ahead of 17-time Grand Slam champion Roger Federer.

Fellow Swiss Stan Wawrinka, who won in Melbourne in 2014, is the fourth seed with Rafael Nadal at five.

French world number nine Richard Gasquet was not among the seedings for the year's opening Grand Slam because of a back injury.
Romania's Simona Halep is the second seed in the bottom half of the women's draw ahead of Spain's Garbine Muguruza and Poland's Agnieszka Radwanska.

Maria Sharapova, the 2008 champion, is fifth seed, while two-time winner Victoria Azarenka of Belarus is seeded at 14.

World number nine Lucie Safarova is skipping the Australian Open because of health problems linked to a bacterial infection, while Italy's Flavia Pennetta, ranked at eight, retired from the sport after her win at last year's US Open.

The 2016 Australian Open runs from January 18-31.

Men

1. Novak Djokovic (SRB), 2. Andy Murray (GBR), 3. Roger Federer (SUI), 4. Stan Wawrinka (SUI), 5. Rafael Nadal (ESP), 6. Tomas Berdych (CZE), 7. Kei Nishikori (JPN), 8. David Ferrer (ESP), 9. Jo-Wilfried Tsonga (FRA), 10. John Isner (USA), 11. Kevin Anderson (RSA), 12. Marin Cilic (CRO), 13. Milos Raonic (CAN), 14. Gilles Simon (FRA), 15. David Goffin (BEL), 16. Bernard Tomic (AUS), 17. Benoit Paire (FRA), 18. Feliciano Lopez (ESP), 19. Dominic Thiem (AUT), 20. Fabio Fognini (ITA), 21. Viktor Troicki (SRB), 22. Ivo Karlovic (CRO), 23. Gael Monfils (FRA), 24. Roberto Bautista Agut (ESP), 25. Jack Sock (USA), 26. Guillermo Garcia-Lopez (ESP), 27. Grigor Dimitrov (BUL), 28. Andreas Seppi (ITA), 29. Nick Kyrgios (AUS), 30. Jeremy Chardy (FRA), 31. Steve Johnson (USA), 32. Joao Sousa (POR)

Women

1. Serena Williams (USA), 2. Simona Halep (ROM), 3. Garbine Muguruza (ESP), 4.   Agnieszka Radwanska (POL), 5. Maria Sharapova (RUS), 6. Petra Kvitova (CZE), 7. Angelique Kerber (GER), 8. Venus Williams (USA), 9. Karolina Pliskova (CZE), 10. Carla Suarez Navarro (ESP), 11. Timea Bacsinszky (SUI), 12. Belinda Bencic (SUI), 13. Roberta Vinci (ITA), 14. Victoria Azarenka (BLR), 15. Madison Keys (USA), 16. Caroline Wozniacki (DEN), 17. Sara Errani (ITA), 18. Elina Svitolina (UKR), 19. Jelena Jankovic (SRB), 20. Ana Ivanovic (SRB), 21. Ekaterina Makarova (RUS), 22. Andrea Petkovic (GER), 23. Svetlana Kuznetsova (RUS), 24. Sloane Stephens (USA), 25. Samantha Stosur (AUS), 26. Anastasia Pavlyuchenkova (RUS), 27. Anna Karolina Schmiedlova (SVK), 28. Kristina Mladenovic (FRA), 29. Irina-Camelia Begu (ROM), 30. Sabine Lisicki (GER), 31. Lesia Tsurenko (UKR), 32. Caroline Garcia (FRA)
Source: AFP