US PGA champion YE Yang stormed into a share of second place, one behind fellow South Korean Kim Do-hoon, after a birdie blitz during the second round of the Volvo China Open.
Yang, making a rare foray on the European Tour, picked up five shots in six holes from the ninth on the way to a six-under 66 and a tie for second alongside Thailand's Thongchai Jaidee and Welshman Jamie Donaldson at 10-under-par.
"I managed to score quite well despite the conditions yesterday and today the conditions were more friendly and I was able to be a little bit more aggressive," said Yang, who became the first Asian man to win a major when he held off world number one Tiger Woods on the final day of last August's US PGA Championship at Hazeltine.
"I think the crucial hole for me was the birdie at number nine as it opened the gate to the back nine performance.
"I also had an opportunity to make birdie on 10 but missed that, but overall with the birdie on nine by overall demeanour and body language towards the game and towards the back nine opened up quite positivity and knowing that I needed to be in the area of 10 or 11 under par, I knew I had to play more aggressively."
Yang's lesser known compatriot Kim is one clear at the top after following his opening-day 64 with a solid 69.
The 21-year-old, who is looking to build on a maiden Korean Tour victory at the SBS Tomato Open last week, had four birdies before finishing off with his solitary bogey of the day at the 18th.
"I thought I would be quite nervous as it is a big tournament but I am very comfortable after two rounds," said Kim, the 2006 Asian Games gold medallist.
"I hope to play well this week and hopefully become the champion. I am not nervous and I feel comfortable after winning last week in Korea.
"I shot 64 last week and I feel I am the hottest Korean player right now."
Donaldson signed for a 68 and Jaidee a 70 to make it a three-way tie for second.
"I have been playing some good golf and I have just got to keep doing the same stuff and hopefully it (a maiden win) will happen," said Donaldson, who has rebuilt his career since losing his European Tour card in 2006.
"Taking the step back to the Challenge Tour gives you the kick that you need.
"You drop down a level and you start realising what you get out of it, which is not a lot financially and physically.
"It gives you a good telling off and you realise where you want to be and where you want to get to. It's just a big reality check that you don't want to be there again."
Spain's Pablo Larrazabal (69) and Finland's Mikko Illonen (67) share fifth place at nine-under-par, while Luxehills Chengdu Open winner Liang Wenchong remained in the hunt to become only the third Chinese winner the event after carding a 70 to sit alone at eight-under.
American Ryder Cup captain Corey Pavin (70) and Malaysian Open champion Noh Seung-yul (68) are a further shot off the pace on seven-under-par, alongside Kim Dae-hyun (67).