Russia's Maria Sharapova has pulled out of this week's WTA Dubai Championships citing a viral illness.
Sharapova said she felt unwell during her run to the Qatar title
The Australian Open champion, 20, won the Qatar Open crown on Sunday and is unbeaten so far in 2008.
The world number five had been due to play her first match in Dubai on centre court in Tuesday's evening session.
"Unfortunately I have been battling a virus for several days and it's reached a point where I'm unable to compete," Sharapova said in a statement.
"I flew to Dubai right after my final in Doha and woke up on Monday feeling really fatigued and stuffed up with a cough.
"After trying to hit a little bit in the evening, I came to the conclusion that I'm realistically not going to be ready to play five matches in five days.
"It's been such a great and healthy start to the year, and I don't want to jeopardise that by making the wrong decisions, as I have in the past.
"This is really disappointing to me, but I do intend to come back to Dubai next year and hopefully have a great tournament."
Former world number one Serena Williams pulled out over the weekend, also blaming illness.
Belgium's Justine Henin heads a strong field at this year's event, where she is joined by Svetlana Kuznetsova, Ana Ivanovic, Jelena Jankovic and Anna Chakvetadze.
World number one Henin is the reigning champion and has won the Dubai title four times in total.