Tiger Woods has confirmed he will not be playing in the Masters next week as he is not "tournament ready" following further back problems.
Woods spent almost 16 months on the sidelines after undergoing major back surgery, and he made a long-awaited return to competitive action in the Bahamas last December.
But he missed the halfway cut in his first PGA Tour outing of 2017 at the Farmers Insurance Open in January, and he completed only one round at the Omega Dubai Desert Classic a week later before withdrawing due to back spasms.
Woods and his team insisted the setback was unrelated to the surgery - the third back operation of his career - but he then pulled out of the Genesis Open in California and missed the entire Florida Swing while having intensive treatment.
He appeared on American television last week and declared he was "trying everything" to be ready for the first major of the season, but he has run out of time to get himself in the required shape to compete at Augusta National.
Woods, who also missed the Masters last year, will be in attendance at the traditional champions dinner hosted by Danny Willett on Tuesday evening, but he will not be teeing up on Thursday.
The four-time winner offered his apologies to Augusta National chairman Billy Payne and expressed regret that he would not be able to play on the 20th anniversary of his record-breaking maiden Masters triumph as a 21-year-old.
A statement on his website read: "Unfortunately, I won't be competing in this year's Masters. I did about everything I could to play, but my back rehabilitation didn't allow me the time to get tournament ready.
"I'm especially upset because it's a special anniversary for me that's filled with a lot of great memories. I can't believe it's been 20 years since I won my first green jacket.
"I have no timetable for my return, but I will continue my diligent effort to recover, and want to get back out there as soon as possible.
"I'd like to pass along my regrets to Billy Payne, the Augusta National membership, staff, volunteers and patrons, that I won't be there. I will be at the Champions Dinner and I look forward to seeing a lot of old friends.
"Augusta National has been a very important place to me and my family for over 20 years, and while I'm disappointed, it will be good to be back there Tuesday."