he 20-year-old Asian Tour rookie eagled the 11th hole but then dropped three shots on the next two holes. However, he finished with birdies on four of his last five holes to sit at 10-under 206 and take a one-shot lead over Sweden's Rikard Karlberg, who also shot a 68.
Indian duo Mukesh Kumar (70) and Manav Jaini (71) were another three shots back in a four-way tie for third place, along with Australia's Unho Park (70) and Jbe Kruger of South Africa (69).
Local favorites and former tournament champions Arjun Atwal and Jyoti Randhawa were six shots off Baek.
Baek, who plays on the Thai domestic circuit, kept the lead despite a bogey and double-bogey on the 12th and 13th holes.
“I came back with two birdies and then made a long birdie on 17 from 45 feet and another good birdie on the last,” said Baek, whose best finish was tied 10th in last week's King's Cup in Thailand.
“It's only a one-shot lead,” Baek said. “I know I will be nervous tomorrow but I'll concentrate on my own game and not look at the crowds. Today I just kept hitting my shots and didn't think of anything and, before I knew it, I was on the last hole. “ Second-place Karlberg recovered from two early bogeys to keep himself in contention.
“I got off to a bad start but after that I started to find my way back,” Karlberg said. “I had a good streak with good shots and easy birdies from holes six to nine.”