The British golfer Rory McIlroy posted the lowest 36-hole score ever recorded at the US Open to grab a commanding six-stroke lead after the second round at the Congressional course in Maryland.
The 22-year-old followed up his opening round of 65 with five birdies and an eagle for a superb 66 to reach the halfway stage at 11 under par, shaving one stroke off the previous US Open record set two years ago.
McIlroy's round could have been even better had he not made a double-bogey six at the final hole after hitting his approach into the water.
However the Northern Irishman, who blew a four-stroke lead at the Masters two months ago, is keeping his feet firmly on the ground.
He says he's well aware there's still plenty of golf to play and knows he'll need to be at his best to be crowned the 2011 champion.
Yang Yong-eun of South Korea, the first Asian man to win a major with his victory at the 2009 PGA Championship, was a distant second but still three shots clear of a group made up of Robert Garrigus, Sergio Garcia, Zach Johnson, Brandt Snedeker and Matt Kuchar.
New Zealand's Michael Campbell missed the cut after blowing out to a 77 on day two.
