Ronnie O'Sullivan has pulled out of the upcoming International Championship to deal a major blow to the richest tournament China will have ever staged.
The reigning world champion, who this week questioned his own decision to return to the tour after a short hiatus, has cited medical reasons for his decision to withdraw from a tournament which begins in Chengdu on Sunday.
"We have been made aware that Ronnie has been unwell. The usual process for players pulling out of tournaments will now be applied," said Jason Ferguson, chairman of the World Professional Billiards and Snooker Association.
"This is a huge disappointment for all of the fans in China who were hoping to see him play. However, there is still an outstanding line-up of the world's best players at the International Championship and it will be a top-class event."
The International Championship offers prize money similar to the UK Championship, with a total fund of £600,000, of which £125,000 goes to the winner.
O'Sullivan, 36, issued a statement through his management, Grove Leisure, to give a brief explanation of his absence.
"I'm very sorry that I had to officially withdraw from the International Championship, due to ongoing health problems," he said.
"I would have loved to be fit to compete in Chengdu but I have been advised by my doctor not to travel.
"I want to sincerely apologise to World Snooker, the sponsors and the fans for the disappointment caused. I look forward to see you all soon."