In the process, the American took over as the new World No. 1, moving past Dustin Johnson and Justin Rose to take the top mantle in the men's game.
Koepka’s apparent grip on the tournament through 54 holes appeared in jeopardy today when struggling through the opening nine holes and at one point was tied for the lead with Gary Woodland but it was a game of two halves for Koepka as he stormed home with a back nine of 29 to win by four shots over Woodland.
With five PGA Tour titles, an additional European Tour victory, two Japan Golf Tour victories and four Challenge Tour wins, Koepka has 12 professional victories in seven different countries – South Korea, United States, Japan, Spain, Turkey, Scotland and Italy.
“I look at where I started, my first pro start was in Switzerland and I don't think I could have said six years later that I would be No. 1 in the world," said Koepka. “I think it's incredible.
“All these places I've won at, we saw a stat yesterday where it was I've cracked the top 1000, 500, 400, 300 and so on, so on, I only cracked any I think the top 10 in the United States, everywhere else has been in a different country and it's probably fitting that I did it in Korea.
“I enjoyed my time on the Challenge Tour, the European Tour, and being here on the PGA TOUR. To be World No. 1 is something I dreamed of as a kid and I don't think this one's going to sink in.
“But it's a cool feeling. I can't wait to come back next year, this golf course is fantastic. It's so much fun to play. It really challenged you. I'm so happy now, I don't even know what to say.
Ryan Palmer and Rafa Cabrera Bello tied for 3rd another two shots behind Woodland.
The Australians performed with great distinction, especially in today’s final round, with Jason Day’s round of 67 resulting in a 5th place finish.
Cameron Smith finished tied for 7th, Adam Scott eagled the last to complete his brilliant final round of 63 and finish tied for 10th and Marc Leishman produced a round of 66 to finish tied for 18th.
Leishman now heads the FedEx Cup points table at this early stage of season 2018/2019.
RULES: LEAVING THE FLAG IN
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