The first two rounds of the 2012 PGA Championship in South Carolina are in the books as of Friday. Tiger Woods, who entered the tournament as the odds-on favorite to win, is holding a share of first place, shooting a 1-under in his second round to finish at 4-under for his first two rounds.

Also holding a share of the lead is Vijay Singh, who shot a terrific 3-under on the day to jump a full 31 spots on the leaderboard. Carl Pettersson entered the day all alone atop the leaderboard, but Friday's 2-over round sank him into the three-way tie. Ian Poulter is alone in fourth place at 3-under, while Rory McIlroy and Jamie Donaldson are in a tie for fifth place at 2-under. McIlroy's second round was was less than ideal, at 3-over.

You can check out the complete leaderboard here.

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