Tiger Woods announced he had lost his battle to be fit for the Masters, saying he was "not tournament ready" for the first major of the year and did not have a timetable for his return.
Woods, whose 14 major titles include four Masters green jackets, has not played since withdrawing from the Dubai Desert Classic on February 3 with ongoing back spasms.
He made his comeback in December after missing all of the 2015-16 season in the wake of back surgery.
But his return has run aground, with the 41-year-old withdrawing from the Genesis Open in Los Angeles in February, the Honda Classic and the Arnold Palmer Invitational in March.
He even cancelled a planned press conference at the Los Angeles tournament, saying doctors had advised him to "limit all activities" as he tried to get his balky back on track.
"Unfortunately, I won't be competing in this year's Masters," Woods said on his website. "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."
Woods's historic 1997 victory at Augusta National, when he was 21 years old, was a watershed for golf.
He became the first black golfer to win a major, the youngest to capture the Masters and he shattered records in winning by 12 strokes with an 18-under par total.