Serena Williams is targeting a return to competitive tennis next January to defend her Australian Open title, but two former stars who became parents question her ability to regain top form so soon after childbirth.

Williams gave birth to a baby daughter on September 1 and would be trying to be ready for play when next year's first Grand Slam event gets under way on January 15 on the Melbourne hardcourts.

Asked if that was a realistic timetable for a comeback, three-time US Open champion Kim Clijsters was dubious. And she retired for two years and had a baby before returning and winning her 2009 crown in New York.

"To me, it wasn't when I had Jada," said Belgian Clijsters. "It all depends. If you set your mind to it, maybe."

One unknown factor about Williams is how taxing the delivery was upon her.

"Depends how the labor and birth went," Clijsters said. "How your body reacts -- everybody reacts different in those situations."

American Mary Joe Fernandez, a runner-up at the 1990 and 1992 Australian Opens and 1993 French Open, noted that Williams, a 23-time Grand Slam singles champion, has been defying the odds for years.

"Maybe see her there," she said. "I couldn't have done it. Serena is an exception to a lot of rules."

Williams is one slam crown shy of matching the all-time record of 24 major Slam singles titles won by Australia's Margaret Court.

Source: AFP