Tiger Woods' anticipated return to the PGA Tour after a fourth surgery to his left knee is up in the air. But his colleagues are confident about one thing — the world's No. 1 could come back even better.

"He isn't going to be worse," said rising star Anthony Kim, who headlines the PGA Tour's season-opening Mercedes-Benz Championship this week in Hawaii with Camilo Villegas, Vijay Singh, Ernie Els and Adam Scott. "We all know it's going to be a long year trying to beat him."

Woods begins the year in Florida, however, where he continues to mend his surgically repaired left knee. Also missing the winners-only Mercedes-Benz are world No. 2 Sergio Garcia, No. 3 Phil Mickelson and No. 4 Padraig Harrington, all forgoing the season opener for rest and practice.

But while Woods is out of action, he isn't out of mind.

"Tiger is Tiger," said Villegas, who won the last two FedExCup playoff events in 2008. "He'll come back strong. Probably stronger. He will probably continue to be No. 1. He'll be just as tough to beat this year as ever."

Woods' 2008 was cut short when he had surgery eight days after defeating Rocco Mediate in a 19-hole playoff to win the U.S. Open in June. A tendon was taken out of his right hamstring and became his left knee's anterior cruciate ligament. Some cartilage damage was tended to and the double stress fracture in his left tibia has healed.

His latest surgery was his second in 2008 — he had cartilage damage repaired in an operation two days after finishing runner-up to Trevor Immelman at The Masters in April. Woods also had left-knee surgery in 1994 to remove a benign tumor and in 2002 to remove a benign cyst.

"Long-term this is the greatest thing that could have happened, to go in there and reconstruct it. Now it's better than it's been in over a decade," Woods said in December at the Chevron World Challenge he hosted.

In the short term, Woods intends to go for a fifth green jacket in April. His hope is to play at least one event before that, possibly in March at the Arnold Palmer Invitational in Orlando, where he is defending champ, or the World Golf Championships-CA Championship near Miami.

Woods began hitting full shots with short irons last month. He will build up strength in the pool, gym and on the golf course.

"I'm actually stronger in my legs than I think I've ever been," Woods said. "But still, the ligament is only going to heal so fast.

"How is the leg going to respond to more hours of practicing, more playing, more holes of play, playing at home? How is it going to recover from day to day to day? All this is unknown."

Mark O'Meara has seen Woods hitting golf balls on the Isleworth range. He liked what he saw.

"I'm not always right, but a lot of times I seem to be right about him, and he'll come back better than he has ever been," he said. "You're going to see some pretty phenomenal things from Tiger Woods the next three years."

That will take some doing since Woods is his own tough act to follow. His U.S. Open win capped a stretch in which Woods won 10 events, finished second twice and fifth once in 13 worldwide starts.

But before his latest surgery, he had trouble stopping his left knee from snapping through impact. With two strong legs — and knees — to stand on, he'll be able to more positively move his weight toward the target, generating power and more accuracy.

"It feels great to have that stability," Woods said. "It's not sliding all over the place. Things that I was dealing with, I don't feel that anymore. I want to become better than I was."