Thailand's Phachara Khongwatmai moved to take a share of the third-round lead with Malaysia's Gavin Green after signing for a three-under-par 69 at the International Series Singapore on Saturday.
Green, who held an overnight three-shot lead, could not extend his advantage further as he succumbed to pressure and returned with a 72 at the Asian Tour sanctioned event.
The Singapore tournament is also part of the new International Series that received US$400 million in funding from the Saudi-backed LIV.
After carding identical rounds of 65 in the first two days, Green admitted to struggling on the third.
"I'm not going to lie. There is pressure. I was trying to push away, it was just hard, I could not get anything going," said the Malaysian.
Unlike his first two days, which were bogey-free and saw 14 birdies, Green only made one birdie on eight, while dropping his first shot of the week on the par-four 13.
"It was such a grind. I couldn't get anything going. Golf is not a game where you can be perfect all the time. But we are still in it, as there are still 18 more holes to go," said Green.
Phachara, meanwhile, stumbled early with a bogey on his second hole. But he recovered well, with birdies on holes five, six, eight and 14 to compile a three-day total of 14-under-par 202 at the Tanah Merah Country Club.
The 23-year-old Thai said he was confident he could clinch his second win on the Asian Tour if he improved his putting.
"If I make a lot of putts, then maybe it's mine. I hit the ball well today but just missed a lot of putts. I hope the putter works tomorrow," said Phachara.