Luke Donald powered into a four-stroke lead after superb 64 on day two of Dunlop Phoenix tournament in Japan.
The Englishman's seven-under-par second round ensured he posted a 13-under halfway total of 129 at the Phoenix Country Club in Miyazaki.
That left him four clear of his nearest rival, local hope Shunsuke Sonoda (66), while another Japanese player, Hiroyuki Fujita (66), sits in third a further two shots back.
Starting on the back nine, Donald made a fast start with birdies at 10, 11, 13 and then 15 to get himself 10-under, before picking up three more shots on the front nine to take control of the event.
European Ryder Cup star Nicolas Colsaerts faded with a 71 on day two and is amongst six players tied for 19th at two-under alongside local favourite Ryo Ishikawa.
American Ricky Barnes and Edoardo Molinari of Italy were amongst the players who failed to make the halfway cut.