Kim Bi-O showed a maturity that belied his youth on Saturday to shoot a five-under-par 67 and take a two-shot lead into the final round of the OneAsia Tour event in Seoul.

The 21-year-old from South Korea sits on a 11-under-par total of 205 after a scintillating third round display on the hilly 6,368m Namseoul Country Club course.

Bi-O, who won the China Masters OneAsia event last year, dropped only one shot all day — a missed four-foot putt on the last giving the chasing pack a hope going into Sunday’s final round.

“I tried really hard to concentrate out there and it went well all day until that bogey on the last,” Bi-o said. “I just want to go out there tomorrow and do the same thing,” he added in comments released by the organisers.

Bi-O scored three birdies either side of the turn to leave him best placed to win the third event of the 2012 OneAsia circuit.

The par-five 14th was pivotal when overnight leader Park Sang-Hyun bogeyed after twice hooking into the woods that line the course.

A birdie by Bi-O meant a two-shot swing and a lead he never looked like relinquishing.

Park, 29, lies alone in second place, with Hwang In-Choon, 37, and Choi Ho-Sung a shot further back at eight-under after both scoring 68s on Saturday.

The OneAsia tour has 14 events this year with a total purse of over $US16 million.