Justin Thomas claimed his second CJ Cup trophy after reigning supreme in South Korea on Sunday.
American star Thomas carded a five-under-par 67 in the final round to triumph by two strokes on Jeju Island.
Playing outside of the United States, where Thomas won the PGA Tour tournament in 2017, the former world number one withstood a duel with runner-up Danny Lee.
Thomas entered the final day tied for the lead alongside South Korean-born New Zealander Lee (69) at Nine Bridges Golf Club.
The pair continued to go toe-to-toe during the final 18 holes, sharing the lead down the stretch, but back-to-back bogeys at the 15th and 16th dashed Lee's hopes.
Thomas birdied three holes on the back nine, capping his triumphant performance with another birdie at the last to finish 20 under for his 11th Tour crown.
Hideki Matsuyama (65), Gary Woodland (66) and Cameron Smith (69) finished in a share of third position, five shots adrift of Thomas.
Three-time major champion Jordan Spieth was unable to maintain his charge following a final-round 71.
Spieth had four bogeys to go with five birdies as he fell four positions into a tie for eighth – eight shots off the pace.
Meanwhile, American veteran Phil Mickelson (68) ended the event tied for 31st, a shot ahead of former world number one Jason Day (71).