Soomin Lee was on course to win his first European Tour event at just his second attempt midway through the final round of the Maybank Championship Malaysia.
The South Korean finished in a tie for third at the UBS Hong Kong Open in October and was playing in his first event as an Affiliate Member at Royal Selangor Golf Club.
He came into Sunday with a three-shot advantage but saw that cut to two at the turn, with a front nine of 34 moving him to 16 under and allowing Marcus Fraser to narrow his advantage.
Miguel Tabuena was then at 12 under, with Richard Bland, Nathan Holman and Peter Uihlein a shot further back.
Lee dropped a shot with a disappointing three-putt at the second but picked it back up on the next following a good drive and an excellent chip after nearly reaching the par five in two.
Australian Fraser chose to lay-up on the same hole but put his approach to within seven feet and rolled in a birdie of his own before saving par on the fourth thanks to a beautiful chip after a wayward tee shot.
Both men birdied the fifth after solid approach shots but Lee gave the gain straight back when he missed from five feet on the next.
The 22 year old had missed from similar range on the second but he was having no trouble from distance and rolled in a lengthy putt on the seventh to re-open a two-shot lead, with Fraser having to hold his nerve to make par on the seventh and eighth.
Filipino Tabuena turned in 33 with a chip-in on the third, a rare birdie on the sixth and an approach to within inches on the eighth before he dropped a shot on the ninth.
American Uihlein was charging through the field at seven under for the day through 15 holes, while England's Bland was two under and Australian Holman was level par.
Julien Quesne and Jorge Campillo were then at ten under, with Stephen Gallacher, Masahiro Kawamura and Robert Rock a shot further back.