Golfer Vijay Singh has slipped to 24th at the World Golf Rankings.

This is the first time in four years that Singh is out of the Top 10. Singh failed to win any major championships this season and at one stage he was the number one ranked golfer in the world.

Singh who had an operation on his knee has also pulled out from the Chevron World Challenge and Australian Open, scheduled for this month.

Tiger Woods remains world's number one golfer.