Seungsu Han clinches first Asian Tour win at Korea Open
The 36-year-old finished the final round with an even-par 71 for a tournament total of six-under-par 278 at the Woo Jeong Hills Country Club.
"This is such a great honour," said Han, who was born in Incheon, South Korea, but moved to the United States when he was 13.
"I first started playing in Korea when I was 13, so the Korea Open means a lot to me," he said.
"I think it is the best tournament in Korea."
Han was trailed by South Korea's Kang Kyung-nam, who also carded a final-round 71 to finish second.
He said the tournament was "tremendously challenging" because he was struggling with foot and throat pains, adding that he tried to avoid looking at the scoreboard.
"It was about being mentally strong and my putting was great, I holed some long ones," he said.
Han's dominance was unexpected, even though he has some notable victories under his belt.
He won the 2017 Casio World Open, one of Japan's biggest events, and three years later claimed the LG Signature Players Championship on the Korean PGA Tour.
Sunday's win also meant Han secured one of the two spots on offer in this year's Open Championship at the Royal Liverpool Golf Club, with Kang claiming the other.
