Tiger Woods will have reconstructive surgery on his left knee that will sideline him for the rest of the 2008 season, the world number one said on Wednesday.

The 32-year-old American defied jabbing pain all week before clinching his 14th major title at the U.S. Open on Monday, winning a 19-hole playoff against compatriot Rocco Mediate.

It was his first tournament in two months since having surgery to clean out cartilage in the knee two days after the U.S. Masters in mid-April.

Woods outlined that he would have reconstructive surgery on his anterior cruciate ligament, which he tore 11 months ago after last year's British Open at Carnoustie.

He also said he would require time off to rehabilitate a double stress fracture of his left tibia that was found last month and attributed to his intense rehabilitation and preparation for the U.S. Open at Torrey Pines in San Diego.

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, Woods said in a statement on his official website ( www.tigerwoods.com ).

I wanted to be very respectful of the USGA (United States Golf Association) 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.

Woods, who has already had three previous surgeries on his left knee, refused to disclose much detail of the pain he clearly suffered at Torrey Pines last week.

MOST MEANINGFUL

However, he rated his major triumph as the most meaningful of his career given the obstacles he faced, an opinion echoed by his swing coach Hank Haney.

I certainly think it's the greatest win he's ever had, Haney told reporters Monday. He had only played 27 practice holes since the Masters and he never hit more than 50 balls a day on the range.

Moments after securing his 14th major title and his 65th career victory on the PGA Tour, Woods admitted he had defied doctor's orders to compete at Torrey Pines.

As far as future ramifications, I'm not really good at listening to doctor's orders too well, he added. Hey, I won this week, so it is what it is.

On Wednesday, he conceded he needed to follow medical advice for the sake of his long-term career.

While I am obviously disappointed to have to miss the remainder of the season, I have to do the right thing for my long-term health, said Woods, who initially had surgery on his left knee in 1994, to remove a benign tumor, followed by arthroscopic surgery in December 2002.

I look forward to returning to competitive golf when my doctors agree that my knee is sufficiently healthy. My doctors assure me with the proper rehabilitation and training, the knee will be strong and there will be no long-term effects.

The driving force behind Woods's career has been his desire to overhaul the record 18 major titles piled up by his childhood idol Jack Nicklaus. Woods now trails by four with only Nicklaus ahead of him.

It's hard to believe I'm in this situation, Woods said. It's hard to believe I've had this nice a run in my career, and hopefully it will continue. I'm going to keep practicing, keep trying to grind and get better.