Tiger Woods is under pressure at the top of the world rankings, and also admits that he faces a struggle to rebuild his game following knee ligament surgery.
The world number one has seen his lead shrink from 11.3 to 3.8 points over Sergio Garcia in second spot.
Woods has topped the rankings for a total of 529 weeks in his career, and the last player to take the top spot from him was recent Chevron World Challenge winner Vijay Singh in June 2005.
But, even more of a concern for the 32-year-old is the injury that has sidelined him since his US Open heroics in June.
"I've got to do a lot of work, and it'll be an arduous task," he said.
"I think I can handle a full swing now, but I'm not there yet. It's going to take a little bit of time."
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Woods, who has been dragged into a verbal exchange with rival Phil Mickelson recently, started hitting balls two weeks ago, but remains cautious at the prospect of hitting a full swing with his driver.
"I don't know how my legs are going to start recovering, then swinging more full, progressing through the ball, and the ball count,” admitted the 14-time Major winner.
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