India's Sania Mirza, who lost in the second round of the Australian Open, dropped two places to be ranked 34th in the Women's Tennis Association (WTA) world rankings released on Monday.
Australian Open semi-finalist Kim Clijsters replaced Lindsay Davenport. The Belgian returned to the number one position for the first time since 2003, one place above Australian Open champion Amelie Mauresmo with American Davenport slipping to third.
The 26-year-old Frenchwoman rose one spot to second after ending her long wait for a first grand slam title by beating Belgian Justine Henin-Hardenne in the final.
Henin-Hardenne, who pulled out of the final in the second set due to stomach illness, moved up one place to fifth, while last year's Australian Open champion Serena Williams dropped 24 places to 39th after losing in the third round in Melbourne.
Former world number one Martina Hingis of Switzerland climbed 232 places to number 117 after reaching the quarter-finals in her first grand slam event since retiring though injury in 2002.