Clijsters moves to No 2, Nadal keeps men's No 1
Australian Open champion Kim Clijsters will move up one spot to No 2 while Serena Williams, who did not defend her title at Melbourne Park, will drop to her lowest ranking in nearly four years when the lists are released on Monday.
Rafael Nadal maintains his No 1 ranking despite his Australian Open quarterfinal loss to David Ferrer, while Caroline Wozniacki held the women's No 1 ranking despite losing to China's Li Na in the semifinals.
Williams, who is recovering from a foot injury, dropped from fourth to 12th, her lowest ranking since March 2007 when she was No 18.
The 13-time Grand Slam singles winner cut her foot on broken glass after her win at Wimbledon in 2010.