Golf: Mickelson is focused on Bridgestone

Phil Mickelson is focused on performing well at the WGC-Bridgestone Invitational this weekend, rather than usurping Tiger Woods at the top of the world rankings.

The 40-year-old left-hander was on course to wrest the world number one ranking from Woods after moving one shot behind halfway leader Retief Goosen at Firestone Country Club in Akron, Ohio.

A top-four finish, coupled with Woods finishing outside the top 44 would see Mickelson climb from second in the world to top spot.

The American was on six under with 36 holes to play after a second round 68 saw him sit joint second alongside Justin Leonard (66) and one behind South African Goosen, who was on seven under after rounds of 67 and 66.

Woods, meanwhile, signed for a two over par 72 and was 13 strokes off the lead on six over and in a tie for 72nd.

Although Mickelson is poised to end Woods' 270-week reign at the top of the rankings, he is first concentrating on finding form for next week's USPGA Championship at Whistling Straits, Wisconsin.

"It would be something I would love to do and ultimately be regarded as number one according to the rankings," said Mickelson. "I know that I've got a great opportunity this week. I know that I'm playing well, and this is my best opportunity but I try not to think about it.

"I want to come out and play well here, get in contention, get sharp, get focused, especially for next week, too. But also, this is a World Golf Championship event that means a lot, and I'd like to make a move this weekend."

Goosen, who has seven PGA Tour career wins and has finished in the top 10 on seven occasions in 2010, was in pole position for victory at the halfway stage.

"This would be a great event to get my first win for the year," said Goosen.

"We'll see what I can do around here on the weekend."

Lee Westwood, who like Mickelson had an opportunity to seize the world number one ranking, withdrew with a ruptured plantaris muscle in his right calf. The 37-year-old Englishman even hinted his participation in the Ryder Cup in October could be in doubt due to the injury, which he suffered at the end of June before managing to finish a distant second behind stablemate Louis Oosthuizen in the Open at St Andrews.