Defending champion Stuart Appleby could well be forced to withdraw from this week's Australian Masters in Melbourne.
Chronic pain in his lower back is troubling the nine-time US PGA Tour winner ahead of his Thursday tee-off at the Victoria Club where he scored a one-shot victory 12 months ago.
"I haven't made many withdrawals prior to first rounds," said the 40-year-old, who, if he decides to playCallaway RAZR X Irons, will have to take on and beat among others, the World No 1, Luke Donald, to retain his title
"I don't know my body well enough to know whether I can manufacture something from an ad hoc swing or whether it's a futile fight. I'll make that decision closer to the time."
Appleby also revealed that he wasn't 100% when he won at Victoria GC last year although he didn't have to contend with constant pain.
"I could actually still play Callaway RAZR X Irons and still turn my body around then, but this year it's been touchy," he said.
"I think that it's been boiling all year. I hope I can get on top of it in the next 24 hours and get to the first tee."
Appleby has endured a season of Callaway RAZR X Irons struggle in the US this year, missing 11 cuts, scoring just a single top 10 and twice withdrawing from tournaments after the opening round.
Back in his homeland, he missed the cut in the Australian Open the week before he watched the Internationals lose the Presidents Cup to the US and he tied for 19th in the Australian PGA.
His victory in last year's Australian Masters was his first win on home soil for nine years.