Brazilian Lucas Lee made an eight-foot birdie putt on the last hole on Saturday to snatch a one-stroke lead after three rounds of the $1 million Thailand Open at Thana City Golf & Sports Club near Bangkok.
Lee's rounds of 65, 67 and 65 leave him 19 under for the OneAsia tournament, ahead of defending champion Chris Wood from England and China's Hu Mu.
Scotland's Simon Yates, who is based in Thailand, celebrated his 43rd birthday with a 64, sharing fourth place at 17 under with overnight leader Scott Strange of Australia who carded a 68.
Lee, 25, who is still seeking his breakthrough victory on a major circuit, refused to be intimidated despite playing with Wood (65) and three-time Major winner Padraig Harrington -- who slipped out of contention with a 75.
"After the first hole you try to forget who they are and try to beat them like any other of the guys, but they do hit the ball very well," said Lee.
"It was a good learning experience. Tomorrow I'm just going to try and be as positive as possible, while also keeping it simple."
Wood, who made his breakthrough professional victory at this tournament last year and followed it up with a win at the European Tour's Qatar Masters in January, said he was delighted so far with his defence of the title.
"I'm really pleased with my efforts so far. I came here to put in a good defence," he said.
"It will take something in the mid 60s to win."
Hu, another OneAsia regular with victory under his belt from China's domestic tour, credited an improved tournament strategy for his performance.
"What I have been doing recently is try to make a game plan for the entire week and then stick to it," he said.
The round of the day belonged to Japan's Katsumasa Miyamoto, who equalled the course record with a 63 after making the turn in 29.
Completed scores after round 2 (par 72).
197 - Lucas Lee (BRA) 65-67-65.
198 - Hu Mu (CHN) 67-67-64, Chris Wood (ENG) 67-66-65.
199 - Simon Yates (SCO) 66-69-64, Scott Strange (AUS) 66-65-68.
200 - Prayad Marksaeng (THA) 68-67-65, Terry Pilkadaris (AUS) 68-64-68.
201 - David Smail (NZL) 69-66-66, Yoshinori Fujimoto (JPN) 67-67-67, David McKenzie (AUS) 65-68-68.