Tiger Woods will miss next week's Masters golf tournament for the first time since he turned professional, after having back surgery to repair a pinched nerve.
The world number one has struggled with the problem since last August and the condition has progressively worsened in recent weeks.
Woods, 38, be away from the PGA tour for several weeks.
A statement on his website said the operation had been successful but he needed to take a rest before playing again.
Woods has not missed the tournament since he made his debut at Augusta National as an amateur in 1995. This year's Masters starts on 10 April.
He failed to finish the Honda Classic at Palm Beach Gardens in early March, quitting after 13 holes in his final round.
Then he tweaked his back again on the last day at the WGC-Cadillac Championship in Miami a week later, tumbling out of contention with a final-round 78 to finish tied for 25th.
He later pulled out of the Arnold Palmer Invitational in the hope that he could play at the Masters.
"It's tough right now, but I'm absolutely optimistic about the future," Woods said. "