Apart from the battle for world number one supremacy, Woods is also wary of the Asian challenge too.

"There are more Asian players here than we have in other WGC events as they are more American and European biased. It's exciting as you see a lot of players who have been playing well on the Asian Tour and Japanese Tour here and that's something which we don't usually see of this quantity," said Woods.

Meanwhile newly-crowned world number one Westwood is aware that his stay at the top will have to be matched by his consistency in play and is concerned that his troubled calf injury might put a damper on his stay at the top.

"Obviously it's very nice to be at the pinnacle of the sport. However, it's one thing getting there and one thing staying there.

"It's going to be tough this week as I've to play well and it may not be easy as I'm bound to be a bit rusty as I've not been playing a lot recently," said the Englishman.

"It's taking a while to recover and it's still not right but I'm getting bored of sitting at home doing nothing and all the people I've seen have said that I can't do any more damage so I've to come out and walk around and that may do it a little bit of good," added Westwood.

While Westwood has to battle the nagging effects of his injury, he is still sanguine about chances at the WGC-HSBC Champions.

"I don't feel any added pressure being world number one. There's pressure but it's what you make out of it. It's unfortunate that my injury happened but you know, it's just a case of managing it at the moment and edging my way through," said Westwood.

Westwood will be playing alongside Asian Tour honorary member Y.E Yang and Mickelson who has signalled his intent of defending his title strongly.

"I've been fortunate to win this tournament and I look forward to playing it every year. I feel like I can put together a good week here and compete for the title," said Mickelson who is making his fourth consecutive appearance in the event that he has won in 2007 and 2009.