Home favourite Kim Kyung-Tae is bidding for a third title when he begins his defence of the GS Caltex Maekyung Open Golf Championship in the South Korean capital on Thursday.
Kim, the world number 52, won last year and in 2007 -- and was also runner-up to Kim Dae-Hyun in 2010 when the billion won ($880,000) tournament first became part of the OneAsia circuit.
The defending champion is likely to face a stiff challenge this year from a mega 159-player field at the hilly Namseoul Golf and Country Club.
Compatriots Kim Dae-Hyun and Kim Bi-o put in impressive practice rounds on Wednesday and Australian Kim Felton says he is back to full fitness.
Also clearly on form is Thai ace Thaworn Wiratchant, who triumphed in the Laos Open last weekend.
Joining the veterans will be young Chinese rising star Zhang Xinjun.
The 24-year-old, who left school at 15 and set his sights on becoming a security guard, came to the game by chance when his first assignment was at a golf course.
"When I picked up a golf club, the best I could hope for was to maybe become a coach and earn my living by teaching golf," he said.
But Zhang took to the game like a duck to water and before long was making a name for himself on China's amateur circuit where he quickly caught the attention of the country's golf authorities.
Zhang said he had to work to compete against some of the world's best players.
"It's much harder than playing as an amateur because I have to take it to a higher level," he said.