Masters champion Phil Mickelson can move past Tiger Woods to become world No 1 by winning this week's $1.71 million top prize at the US PGA Players Championship.

The 39-year-old US left-hander could end a five-year rankings reign by Woods with a victory if Woods, a 14-time major champion who is coming off a sex scandal and five-month layoff, finishes outside the top five at the Players.

Mickelson is at a career-best second in the rankings while the American just behind him, Steve Stricker, announced on Monday he was pulling out of the $9.5 million tournament at TPC Sawgrass because of a sore right shoulder.

Mickelson, a four-time major champion, captured his third Masters title last month and last weekend settled for second behind Northern Ireland's Rory McIlroy to put himself in position to pass Woods, who missed the cut last week.

Only 12 men have held the top spot since the world rankings were instituted in 1986.

After missing the cut for only the sixth time in his pro career, Woods took part in a rare Monday practice, playing the front nine at Sawgrass with Jay Haas and Australian Rod Pampling.

Pampling said Woods felt his own game has improved after the worst 36-hole score of his career last week at Quail Hollow, where he missed the cut by eight shots after a second-round 79, his second-worst pro round.

"(Woods) said it's a lot better than what it was last week," Pampling said. "Early on he hit a couple really solid tee shots. I don't think he hit any of those last week.

"I'm sure he's a lot happier with the way his game is. That's all it takes. If he starts feeling happy with how he's doing out there, he'll be right up there again."

Haas said Woods was experimenting and studying the course, adding, "I wouldn't take too much into what he did".

Woods, the 2001 Players winner, has faced only one other potential dethroning in the past two years, that being last year at Doral after his injury layoff following a 2008 US Open victory.

Spain's Sergio Garcia was in position to overtake Woods with a victory in the World Golf Championship event if Woods missed the top 10, but neither happened.

Woods missed five months in the wake of a sex scandal that saw him admit to multiple mistresses after more than a dozen women claimed sexual affairs with the married father of two. Woods made his return at last month's Masters.