Last year's Australian Open runner-up Jo-Wilfried Tsonga could miss next week's tournament after a back injury forced him out of the Sydney International on Thursday.
The Frenchman twice needed treatment to his lower back during his quarter-final win over Simone Bolelli on Wednesday and then pulled out of his semi-final against Jarkko Nieminen on Thursday after the problem deteriorated overnight.
"I decided this afternoon because the pain, it's too much, I cannot play," Tsonga told a news conference. "I saw my physio a lot yesterday. I saw the physio from the ATP. I saw the doctor and they told me it's difficult to play like that.
Tsonga, seeded fifth for the Australian Open next week, has been troubled by back problems in the past and was unsure whether he would be able to take his place in the first grand slam of the year, starting in Melbourne on Monday.
"I hope it will not affect me for the Australian Open but I don't know" he said. "I had a problem with my disc a long time ago and sometimes it happens.
"I just have to wait and come back on the court when I feel better. I can't do anything for the next two days. I will stay maybe in my bed and hope I will be better."
Tsonga, 22, was one favourites to win the Australian Open after beating Rafael Nadal to reach last year's final, which he lost to Novak Djokovic, and winning the Paris Masters in November.