Rafael Nadal intends to play his second-round match at the Shanghai Masters against Feliciano Lopez despite being diagnosed with appendicitis.
Nadal, 28, complained of stomach pains on Sunday and doctors subsequently confirmed he had the condition.
He has been given antibiotics to enable him to face Lopez on Wednesday, but will require surgery in the future.
"I'm in Shanghai. I am here to play a tournament. If I don't play, I don't have the chance to win," Nadal said.
"It seems like everything is under control now. The normal thing is for the improvement to continue."
World number two Nadal has struggled with injuries since the summer and missed the US Open with a wrist problem.
He has competed just once, at the China Open last week, since he was beaten by Australian teenager Nick Kyrgios in the fourth round at Wimbledon.
|Race to make ATP Finals|
|Andy Murray is currently ninth in the race to reach the November ATP Finals - the top eight qualify for the season-ending event.|
|However, Murray might need to rise to seventh with the eighth spot going to a 2014 Grand Slam champion ranked between eighth and 20th. Croat Marin Cilic, who won the US Open, is currently ranked sixth.|
Nadal has yet to decide whether an operation on his appendix will force him to end his season early.
However, should he choose to do so then it would benefit Andy Murray's chances of playing at the World Tour Final.
Murray's current position of ninth in the race to qualify would be enough if Nadal pulls out of the event.