Tiger Woods is still recovering from back surgery and will miss next week's Masters at Augusta.
The four-time winner of the year's first major has not played any competitive golf since August last year, and has since gone under the knife on two occasions in an attempt to find a long-term solution to the problem.
The 40-year-old Woods maintains that he is "making progress" but has refused to put a timescale one his return.
"I've decided it's prudent to miss this year's Masters," Woods said in a statement to the press on Friday.
"I've been hitting balls and training daily, but I'm not physically ready."
The former world number one missed the 2014 Masters with a similar problem, but featured at last year's tournament at the famous Georgia course, finishing in a tie for 17th.
"I've said all along that this time I need to be cautious and do what's best for my long-term health and career," he added. "Unfortunately, playing Augusta next week wouldn't be the right decision.
"I'm absolutely making progress, and I'm really happy with how far I've come, but I still have no timetable to return."
Woods, whose ranking has dropped to 472nd in the world, will attend the Champions Dinner on Tuesday.
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