|Watney is leading at 13-under heading into the final day [AFP]
American Nick Watney broke free of the chasing pack to open up a three-stroke lead after the third round of the US PGA Championship.
Watney made eight birdies and two bogeys in a superb round of 66 to head into the final day leading at 13-under-par after a perfect sunny afternoon on the shores of Lake Michigan that proved ideal for low scoring.
More than 50 players finished under par with nine within five strokes of Watney, setting the stage for a dramatic final day to the last major of the year.
Northern Ireland's Rory McIlroy underlined his reputation as one of the top emerging players in world golf with a 67 to end the round at 10 under on Saturday, tied for second with big-hitting American Dustin Johnson, who also carded a 67.
China's Liang Wenchong shot a flawless round of eight under 64 to better the course record jointly held by Darren Clarke and Miguel-Angel Jimenez and join Australia's Jason Day (66) and Germany's Martin Kaymer (67) at nine under.
Australia's Steve Elkington, who won the PGA Championship 15 years ago, wound back the clock to reach eight under and join the American trio of Jim Furyk (70), Zach Johnson (69) and Jason Dufner (69).
Hole in one
American Tom Lehman, this year's Senior PGA champion, also struck one for the older generation with the shot of the day, a hole in one on the par-three 17th.
Tiger Woods birdied his last two holes to end an exhausting day tied for 31st at three under as his hopes faded of ending a year dominated by revelations about his private life on a high.
The world number one played the last 12 holes of his uncompleted second round in the morning then returned after lunch to play his third round and said he was satisfied his game was heading in the right direction despite not winning a tournament this year.
"I feel so much better, how I'm hitting the golf ball now," he said.
"The striking, the sound, the feel – more than anything, it feels good."
The perfect weather conditions also allowed tournament officials to get the championship back on schedule after nearly six hours were lost on the first two days because of heavy morning fog.
The third round was played in groups of three off split tees because of the delays to the second round, which American Matt Kuchar eventually led by a shot from Watney.
Kuchar ended the day six shots off the pace at seven under after a disappointing 73 in the third round.
The winners of this year's last two majors, British Open champion Louis Oosthuizen and US Open winner Graeme McDowell, both missed the cut.
Last year's PGA winner, South Korean Yang Yong-eun, also made an early exit, along with the 2008 champion Padraig Harrington, who double-bogeyed the last hole to jeopardise his chances of making the European Ryder Cup team.