Kiradech Aphibarnrat cut Justin Rose's lead at the Indonesian Masters to just two shots after a flawless eight-under-par 64 in Friday's second round.
Aphibarnrat carded his bogey-free lap of Royale Jakarta Golf Club in the morning but Rose was hampered by a weather delay in the afternoon.
Bad light meant Rose couldn't finish his round off and he'll have to return to the course early on Saturday morning to complete his final two holes.
Thai star Aphibarnrat started his round from the 10th tee on Friday and picked up early birdies at 12 and 13. He then made five in a row (18, 1, 2, 3, 4) before a final red number at the 8th.
After reaching 12-under 132 at halfway, Aphibarnrat said: "I have been hitting it good all week and playing some good golf. I am happy with the five birdies in a row that I made and only missed two birdie putts overall.
"The conditions were good at the start but at the end it was very hot and humid. I will just play my own game and keep myself up there on the leaderboard over the next two rounds."
Rose still leads the way on 14-under and added another five birdies against a single bogey on Friday following his brilliant opening 62.
The Englishman made gains at 2, 5, 6 and 9 before adding another at 11. But the delay seemed to hurt his rhythm and he dropped his first shot of the day at the par-3 15th.
Giwhan Kim of South Korea shot a 68 to reach 11-under and Zimbabwe's Scott Vincent is on the same number but still has four holes to complete.
Pachara Khongwatmai is solo fifth on 10-under, five shots behind Rose.
Rose is 1.001 to complete victory on the weekend, with Aphibarnrat 1001.00 and Vincent 251.00.
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