Tiger Woods will miss the rest of the season because of a left knee that will require more surgery, he said in a statement on his Web site.
"I know much was made of my knee throughout the last week and it was important to me that I disclose my condition publicly at an appropriate time," the statement said. "I wanted to be very respectful of the USGA and their incredibly hard work, and make sure the focus was on the U.S. Open.
"Now, it is clear that the right thing to do is to listen to my doctors, follow through with this surgery, and focus my attention on rehabilitating my knee."
The surgery will be to repair the anterior cruciate ligament in his knee, a painful and debilitating injury that takes months to heal. The statement said his prognosis was good.
Woods also will need the time off to heal and rehabilitate a double stress facture in his left knee discovered before he played his last tournament before the Open, the Memorial.
Woods had surgery to clean out cartilage April 15. The site said the stress fractures also were related to the training regimen he put himself through prior to the Open, which he won in a 19-hole playoff Monday over Rocco Mediate.
Woods was last seen in public late Monday afternoon walking with a pronounced limp across Torrey Pines toward the parking lot, the U.S. Open trophy in his arms.
Upcoming surgery makes his 14th major title even more staggering—despite the stress fracture, he managed to win a U.S. Open that required 91 holes over five days.
Woods played only seven times worldwide this year and won five of them.
He will miss a major championship for the first time in his career and will not be available for the Ryder Cup in September.
-- The Associated Press contributed to this report.