As the leaders approach completion of the back nine, there have been some big changes on the leaderboard at the 2012 PGA Championship. While the day opened with Tiger Woods, Vijay Singh and Carl Pettersson tied for first, only Singh remains there. He's currently tied for the lead with Rory McIlroy, who has moved up the rankings after shooting 4-under on the front nine. Pettersson is holding on in fourth, even through eight holes, but Tiger Woods has struggled and slid into a tie for 11th place. Woods had a bogey on holes four, give and six, placing him 3-over through seven.
Former Arizona State Sun Devil Phil Mickelson is 1-over for the day though 11 holes, putting him +1 overall and currently tied for 21st place. There's a lot of golf left to play, so it's still anyone's tournament.
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