DONGGUAN (China), Nov 2: Louis Oosthuizen shot a blistering 9-under 63 to set a new 36-hole World Golf Championship record and open up a commanding five-stroke lead at the HSBC Champions on Friday.

The 2010 British Open champion, the co-leader overnight, had eight birdies and an eagle to offset one bogey at Mission Hills.

He sits at 16-under 128 overall, the best 36-hole round score in WGC history, surpassing the 15-under marks by Tiger Woods at the 2000 Bridgestone Invitational and the 2006 Cadillac Championship.

Ernie Els (63) jumped from 19th place after the opening round into a share of second with Australian Adam Scott (68) at 11 under.

Els made seven birdies on the front nine to card a 29, matching his lowest nine-hole score in a US PGA Tour-sanctioned event, which he also achieved at the 2002 British Open.

Shane Lowry (68) and Jason Dufner (66) were in fourth place, six strokes behind the leader at 10 under.

Phil Mickelson (69) double-bogeyed his final hole to fall into a share of sixth with Dustin Johnson (68) after moving into contention with two eagles on the front nine.

Oosthuizen again made the most of the five par-5 holes on the Olazabal Course, birdieing four and making eagle on the 566-yard seventh. He birdied all five par-5s in the first round on Thursday.

The South African nearly had a second eagle on Friday, too. After hitting his second shot into a bunker on the par-5 ninth, he hit a difficult chip shot over a ridge and onto the green that rolled 15 feet and missed the pin by inches.

Peter Hanson and Bubba Watson fell off the pace after trailing by one coming into the day. Hanson slipped to 12th place after carding a 71 and Watson plummeted to 17th after triple-bogeying the tricky par-5 15th and finishing with a 72.

Leading second-round scores:

128 — Louis Oosthuizen (South Africa) 65, 63.

133 — Adam Scott (Australia) 65, 68; Ernie Els (South Africa) 70, 63.

134 — Shane Lowry (Ireland) 66, 68; Jason Dufner (US) 68, 66.

135 — Phil Mickelson (US) 66, 69; Dustin Johnson (US) 67, 68.

136 — Scott Piercy (US) 68, 68; Thorbjorn Olesen (Denmark) 71, 65; Bill Haas (US) 69, 67; Luke Donald (Britain) 68, 68.

137 — Prom Meesawat (Thailand) 67, 70; Martin Kaymer (Germany) 68, 69; Ian Poulter (Britain) 69, 68; Lee Westwood (Britain) 70, 67; Peter Hanson (Sweden) 66, 71.

138 — Thongchai Jaidee (Thailand) 70, 68; Wu Ashun (China) 68, 70; Gonzalo Fernandez-Castano (Spain) 71, 67; Carl Pettersson (Sweden) 70, 68; Bubba Watson (US) 66, 72.

139 — Keegan Bradley (US) 71, 68; Jang Ik-Jae (South Korea) 68, 71.

140 — Yuta Ikeda (Japan) 70, 70; Hiroyuki Fujita (Japan) 73, 67; Paul Lawrie (Britain) 69, 71.

141 — Marcel Siem (Germany) 71, 70; Thomas Aiken (South Africa) 68, 73; Gaganjeet Bhullar (India) 73, 68; Marc Leishman (Australia) 73, 68.

142 — John Senden (Australia) 72, 70; Justin Rose (Britain) 72, 70; Julien Quesne (France) 71, 71; Thaworn Wiratchant (Thailand) 72, 70; Greg Chalmers (Australia) 71, 71; Thomas Bjorn (Denmark) 72, 70; Tadahiro Takayama (Japan) 73, 69.

143 — Brendan Jones (Australia) 74, 69; Brandt Snedeker (US) 72, 71; Jeev Milkha Singh (India) 72, 71; Han Lee (US) 73, 70; Francesco Molinari (Italy) 74, 69.

144 — Rafael Cabrera-Bello (Spain) 75, 69; Zhang Xinjun (China) 75, 69; Scott Hend (Australia) 70, 74; Robert Garrigus (US) 76, 68; Garth Mulroy (South Africa) 70, 74; Nick Watney (US) 72, 72; Bernd Wiesberger (Austria) 72, 72; Joost Luiten (Netherlands) 72, 72.

145 — Marcus Fraser (Australia) 73, 72; David Lynn (Britain) 76, 69; Liang Wenchong (China) 72, 73; Toshinori Muto (Japan) 74, 71; Jamie Donaldson (Britain) 71, 74.—Agencies