20-year-old Kim Joo-hyung became the second-youngest player since 1932 to win a PGA Tour event – trailing only Jordan Spieth – as he produced a final-round 61 to run away with a five-stroke buffer and claim the Wyndham Championship at 20 under.

In doing so, he became the event's youngest ever winner, and after entering the last tournament of the season ranked in the 400s in the FedEx Cup standings, he booked his place in the playoffs later this month.

His final round included an incredible front-nine score of 27, with six birdies and an eagle, and making his win even more remarkable is the fact that he started his week with a quadruple bogey from his opening hole on Thursday.

Speaking to CBS after stepping off the final green, Kim said his ability to keep a sense of humour about his rough start was the key to bouncing back.

"I stayed very patient this week," he said. "I felt like after that quad, once I started to laugh it off I could feel like I was in a much better mental state. 

"Instead of being angry and depressed I just stayed in the moment – I can't believe I won with a quadruple bogey on the first hole – hopefully that doesn't happen again.

"It's definitely a week I will remember forever."

He added: "it was a hard day – I didn't know golf was this stressful before."

Finishing in a tie for second was Kim's South Korean compatriot Im Sung-jae and American John Huh at 15 under, with Ben Griffin alone in fourth at 14 under.

American trio Max McGreevy, Russell Henley and Taylor Moore tied for fifth at 13 under, and there was another two-stroke gap to the group rounding out the top-10 at 11 under consisting of England's Tyrrell Hatton, Australia's Cameron Percy, India's Anirban Lahiri, and Americans Brandon Wu and Chesson Hadley.

Germany's Stephan Jaeger posted Sunday's second-best round with a 62 to finish tied for 13th at 10 under, and Canada's Corey Conners produced a pair of 66s on the weekend to sit on the fringe of the top-20 after scraping through right on the cut-line, tied with Will Zalatoris at nine under.