Phil Mickleson isn't the only one capable of replacing Tiger Woods as world golf number one.
For the second straight week, Woods is looking over his shoulder at two players who can end his record 270-week run at the top of the world golf rankings, with Mickleson and another American Steve Stricker in contention.
Mickelson would reach No. 1 for the first time, with five scenarios.
A win in the final major of the year, the U.S. PGA Championship which starts on Friday would give him top spot.
Finish runner up, with Woods outside the top three.
A top three finish with Woods outside the top eleven.
A fourth place finish with Woods outside the top 46 or a a two-way tie for fourth with Woods missing the cut.
Stricker has a tougher assignment.
He needs to win the tournament with Woods finishing outside the top 24 and Mickelson out of the top three.