Martin Kaymer, who had been near-flawless with his golf over the first two days, survived three early bogeys and a faltering finish to lead the U.S. Open by five shots after this morning's third round (NZT).
In pursuit of his second major title, the 29-year-old German conjured a miraculous eagle at the par-five fifth on the way to a two-over-par 72 in blazing sunshine at Pinehurst Resort where scoring was at its most difficult for the week.
With very little margin for error on approach shots into domed greens running increasingly fast and firm, Kaymer bogeyed two of his last six holes but sank a six-foot birdie putt at the 18th for an eight-under total of 202 in the year's second major.
''It was good,'' the former world number one told NBC after covering the back nine in one-over 36. ''I didn't play as good as the first two days, but I kept it very well together.
''I felt like today if you have 25 or 30 feet (with approach shots) on every green, you've done well. The USGA put the pins in very, very tough positions.
''On 18 it was probably the easiest pin today and, fortunately, I could take care of it.''
Kaymer, a commanding six strokes clear overnight after setting a tournament low for 36 holes with a 10-under aggregate of 130, finished five ahead of Americans Rickie Fowler and Erik Compton, whose 67s were the best of the round.
Swedish world number two Henrik Stenson and long-hitting American Dustin Johnson were a further shot back at two under after carding 70s on a day when Fowler and Compton were the only players in the 67-man field to dip under par.
''Very, very pleased with today's work,'' Fowler told reporters after a five-birdie display. ''Swing-wise, I didn't drive it very well today but I kept it in play and stayed out of trouble when I could.
''I can put myself in contention with the rest of the group, and see what Martin does,'' Fowler said of Sunday's final round.
''If he goes out and posts double digits (under par), it's going to be impossible for us to catch him. It's like a second tournament going on.''
Reigning U.S. Open champion Justin Rose of England inched his way back up the leaderboard with an even-par 70 to end what is traditionally known as 'Moving Day' at the majors at one over, nine strokes off the pace.
Australian world number one Adam Scott (73) and 2011 winner Rory McIlroy (74) did not fare as well as they finished a further two shots back at three-over 213.
Tricky pin positions, many of them tucked away in the corners of Pinehurst's infamous turtleback greens, and increasingly slick conditions presented a daunting challenge for the players in the third round.
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