Mickelson finished tied for 41st in the HSBC Champions in Shanghai, hurting his efforts to overtake Lee Westwood for the top ranking. "I didn't play the best last week, but I seem to play better the second week of my two-week stretch and hope to put it together this week," Mickelson said.
The Masters champion acknowledged he hasn't "played the way I liked to this year other than the win in Augusta" and will face another daunting field in the $6 million event.
Fellow 2010 major winners Graeme McDowell and Martin Kaymer will be among the 204-man field, as will defending champion Ian Poulter, Francesco Molinari - fresh off his win at the HSBC Champions - plus Asia's first major winner YE Yang, and three-time major winner Padraig Harrington.
Kaymer and Mickelson, ranked third and fourth respectively, are vying for the No. 1 spot held by England's Lee Westwood. But Poulter also has designs on top spot despite his current ranking of 15. The top ranking was out of reach in the years when Tiger Woods was at his peak, but now Poulter sees a window of opportunity.
"Everybody is now in the frame to push forward," Poulter said. "With that in mind, anybody in the top ten can find themselves moving up the world ranking higher enough to contend for that No 1 spot. And that's something I'm aiming for."
The field for the jointly sanctioned European Tour and Asian Tour event will be spread over two courses this year in Singapore, with one round at the tighter Tanjong course and three at Serapong. The number of players meant not all will be able to get in practice rounds.
Meanwhile, Tiger Woods is bullish over his prospects heading into this week's Australian Masters. "I've got a pretty good chance of winning events if I play the way I know I can play," said the reigning champion. "I put together a really good round at the Ryder Cup on the Monday and a shared two good bookend rounds (in the HSBC Champions event in Shanghai] last week, so things are shaping up."