French Open champion Rafael Nadal has withdrawn from next month's Chennai Open as he struggles to overcome a persistent foot injury.
The 19-year-old Spaniard first sustained the problem in the Madrid Masters final in October and withdrew from the Masters Cup in November.
He was expected to return in Chennai but doctors have advised against it.
Nadal must now prepare for the first Grand Slam of 2006, the Australian Open, starting on 15 January.
World number nine Ivan Ljubicic will replace Nadal in the 32-man draw for the Chennai event, which starts on 2 January.
The 2005 season was a highly productive one for Nadal, who won 10 titles.
"Both my medical team and I have been working very hard during the last few weeks so that I could participate at Chennai," he said.
"But my doctor has now recommended that I don't play and it's my misfortune that I can't make it."
Meanwhile, the talented left-hander has donated $25,000 (£14,450) towards a relief fund in Chennai for victims of the tsunami.