"She notified us today that she won't be recovered in time to compete," tournament spokesman John Lindsay said.

Switzerland's Hingis won the last of her five Grand Slam titles at the 1999 Australian Open and has reached the past six singles finals.

The 22-year-old said in October that she would take an indefinite break after a poor run of results following surgery in May that kept her out of the French Open and Wimbledon.

A former U.S. Open and Wimbledon champion, Hingis was scheduled to make her comeback at the January 13-26 Grand Slam event in Melbourne next year.

Hingis won her third successive Australian Open title in 1999 and was a beaten finalist in the past three years in Melbourne.

"We were surprised, but naturally very pleased, when Martina submitted an entry for the Australian Open 2003 given her current injury problems," Australian Open chief executive Paul McNamee said in a statement on Tuesday.

"However it sent out a strong message that she desperately wanted to come down to Australia to play in our Grand Slam.

"Martina has an amazing record at the Australian Open having played in the last six singles finals and I'm sure she would have relished the challenge of trying to make a seventh consecutive final against such a strong women's field.

"We wish her all the best in her recovery and look forward to welcoming her back in 2004."

A former world number one at age 16, Hingis conceded her comeback in August this year from ankle surgery had been too soon and added she would not play any more tournaments in 2002.

"I need to free my mind," Hingis said in October.

She dropped outside the top 10 of world rankings in October for the first time in six years, down to number 11, and is currently ranked 10th.

As power hitters Serena and Venus Williams dominate women's tennis, the slightly-built Hingis (1.70 metres tall, 59 kilograms) has relied on style and savvy more than strength.

"I won't have to turn into a bodybuilder, covered in bulging muscles," Hingis said after another Australian Open singles final loss at the start of this year.

"I just have to get better at what I am already good at - and that is tactical awareness."