MELBOURNE, Australia, -- The World No.1 Rafael Nadal from Spain will begin his Australian Open campaign as the top seed in the men's singles while Caroline Wozniacki comes to Melbourne as the top seed in the women's singles.

According to the seeds list released here on Thursday, the reigning champion and 16-time Grand Slam winner Roger Federer will lead the other half of the main draw as the second seed in the men 's singles. Serbia's World No. 3 Novak Djokovic has been seeded third followed by Swedish Robin Soderling and British top player Andy Murray on the fourth and fifth position.

Defending women's singles champion Serena Williams, ranked fourth in the world, announced her withdrawal from the tournament due to a foot surgery, her sister Venus Williams, therefore, was seeded fourth as the world's fifth-ranked women's singles player.

Russia's World No. 2 Vera Zvonareva will be the second seed while Belgian Kim Clijsters will vie for a consecutive Grand Slam title after crowning at the US Open last season. Kim's compatriot, last year's runner-up Justine Henin will come as the 11th seed. The former World No. 1 is now ranked 13th in the world after coming back from a retirement in January, 2010.

China's top player Li Na, who achieved her personal best by reaching the semifinals last year, has been seeded ninth while the other Chinese semifinalist Zheng Jie gave up this year's tournament in order to recover from a wrist surgery.

The official draw for Australian Open 2011 will take place at Melbourne Park on Friday while the competition will kick off Monday.