Tiger Woods hits an iron shot from the third tee box at TPC Sawgrass on May 12, shortly before being forced to quit. ((Streeter Lecka/Getty Images))

Tiger Woods is using crutches and wearing a protective boot on his left leg to make sure he's healthy enough to play the U.S. Open.

Woods doubts he'll play the Memorial next week in Dublin, Ohio, but expects he'll be "ready to go" for the U.S. Open June 16-19 at Congressional.

Woods is counting on proper treatment and rehab. He is bothered by pain in his left knee, left Achilles' tendon, tightening in his calf, and sore lower back. He says doctors have not mentioned leg surgery.

"I've had four surgeries on it," Woods said. "Obviously, it's not what it was when I was little."

Woods said he'll start training by the end of next week. How his leg responds will determine when he can start hitting balls again — all but ruling out the Memorial.

That means Woods would go to the U.S. Open with little competition, although this is nothing new for him.

In 2008, he had arthroscopic surgery after the Masters and didn't play again until the U.S. Open. Doctors discovered a double stress fracture in his left tibia in the weeks before the major. Going against his doctor's advice, Woods not only played the U.S. Open, he won it at Torrey Pines in a 19-hole playoff.

Now he says his left leg is not nearly as bad as it was then. His golf, however, is a different story.

In the 11 tournaments Woods played before the U.S. Open, he won eight times, was runner-up twice and didn't finish out of the Top 5. In the 11 tournaments before this U.S. Open, he has only five finishes in the Top 10.

Woods said he was more worried about his health in 2008.

"I'm a lot better off," Woods said. "I feel that, in the next week or so, I can start getting back toward that and start practising pain free.

"That's where I'm at."

Woods spoke Tuesday at Aronimink Golf Club to promote the upcoming AT&T National.

Woods withdrew after only nine holes this month at The Players Championship. He also fell out of the top 10 rankings for the first time in 14 years.

He has been No. 1 for 623 weeks in his career, by far the longest of any golfer since the rankings began in 1986. He had been No. 1 from June 2005 until Lee Westwood of England supplanted him last November.

"I haven't played," Woods said. "It's one of the reasons I've fallen I've far as I have.

"When I did play, I haven't played well. Winning takes care of all of that."

He acknowledged he did come back too early for The Players Championship. Woods' status was borderline for the tournament, but he pressed on and did further damage. That's why he's shut himself down for the Open.

"It'd certainly be nice to come up here and play practice rounds and do all the other prep I do for the majors," he said.

Woods posted on Twitter that he would donate $1 million US to his foundation if no reporters asked him about his leg. There was no chance of that on the very first question. Woods later posted on Twitter he would donate the money anyway.