South African Louis Oosthuizen left Adam Scott and the field in his wake with a 63 in the second round of the WGC-HSBC Champions on Friday.
Oosthuizen's nine-under-par round lifted him to 16 under overall - a commanding five-shot lead over joint overnight leader Scott of Australia and fellow South African Ernie Els.
Oosthuizen's round, including eight birdies and an eagle at the par-five 7th, was a course record and puts him in pole position to beat world No.1 Rory McIlroy in the Race to Dubai at the halfway mark of the tournament.
Despite his advantage, the 2010 British Open champion is not taking anything for granted.
"Looking at the leaderboard, there's so many great players up there. It's far from over. It was probably the same at The Open," the world No.11 said.
"With this tournament I'm in a great position to win it, but it's not even crossed my mind at the moment. There's still a lot of golf to be played, and I need to put myself in a great position going down the back nine on Sunday."
The 30-year-old holed a 50-foot putt for his eagle and then nailed a 30-foot putt at the next hole for birdie at Mission Hills in China on Friday.
Scott started on fire with four birdies in the opening seven holes but such was the quality of Oosthuizen's round he slipped six shots back after bogeys at the 12th and 13th before birdies on 15 and 16.
British Open champion Els was on track for a fabled 59 after seven birdies on the front nine but could manage only two more on the run home to join Oosthuizen with the course record, and Scott in a tie for second.
"I obviously had a good start and all of that, but I wish I can always play like that," said Els.
Ireland's Shane Lowry and American Jason Dufner signed for 10-under overall to share fourth, while two-time winner Phil Mickelson slipped back to nine under with a double-bogey at the last following a pair of eagles on No.6 and 14 in his first appearance since the Ryder Cup.
Reigning champion Martin Kaymer of Germany is in the hunt at seven under while Australians Marc Leishman (three under), John Senden, Greg Chalmers (both two under) and Brendan Jones (one under) are further down the leaderboard.