Tiger Woods has ruled out playing at the Masters, saying he is not yet ready to return to competitive action.
The American 14-time major champion has been sidelined since February with a back injury, which has threatened to derail his career in recent years.
Woods, who missed all four majors last year, said he would be absent for the Masters, an event he has won four times.
"Unfortunately, I won't be competing in this year's Masters," he said in a statement.
"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."
Woods last won a major in 2008, while his most recent success at the Masters was in 2005.