South Korea's 'Tom' Kim Joo-hyung announced his arrival on the PGA Tour and cemented his rising-star status in the process with an emphatic five-shot victory over compatriot Im Sung-jae and John Huh of the US at the Wyndham Championship on Sunday.

At 20 years, 1 month and 17 days, Kim became the second-youngest winner since World War II behind Jordan Spieth (2013 John Deere Classic) and the first born in the 2000s to win on the tour after closing with a stunning 61 for a 20-under winning total.

After starting with a quadruple bogey on Thursday－becoming the first player on record (since 1983) to make a quadruple or worse on the first hole and then going on to win－h(huán)e has now qualified for this week's lucrative FedExCup Playoffs.

On the previous Sunday, he secured enough FedExCup points as a so-called "special temporary member" to earn his PGA Tour card for the 2022-23 season.

"It's crazy," said Kim. "I mean, I've never won a golf tournament starting with a quad and here we are. I played great this week. It was hard to stay in the moment in the final round just knowing that I was so close, but I never let my guard down until I holed that putt on 18."

Kim returned early Sunday to complete the remaining eight holes of the weather-disrupted third round with a 68 and trailed third-round leader Im by two.

Nicknamed Tom after Thomas the Tank Engine, due to his fondness for the locomotive character from a British children's book series, Kim charged out like a bullet train in the final round, shooting six birdies and an eagle for an outward 27 to take control of the tournament at Sedgefield Country Club in Greensboro, North Carolina.

With a hot putter in hand－h(huán)e ranked first in the "strokes gained: putting" category at the tournament－Kim made bogey on 10 before birdies on 15 and 16 allowed him to coast home to a winner's check of $1.3 million.

He will also rise to No 21 in the world rankings and has put himself in contention for a spot on the International Team for the Presidents Cup clash against Team USA at Quail Hollow in Charlotte, North Carolina, next month.

"It's been a hectic month and a lot of things have changed, for sure," said Kim, who was playing for a fifth successive week and will now feature in at least two more FedEx Playoffs tournaments－the St. Jude Championship (top 125 players) and the BMW Championship (top 70)－due to his FedExCup ranking of 34th position.

"Like I've expected so much of myself and so does my team, we expect the highest. And it hasn't been the easiest. It might look easy for a lot of people, but it's a lot of work behind the scenes just from the manager doing so much beyond for me and my family who put in sacrifices," added Kim, whose nine previous pro wins were achieved in countries such as Malaysia, Singapore, India, Indonesia, the Philippines, Pakistan and South Korea.

"This is just a start for me and I still have so much I want to accomplish and this is just－I bought the car, we bought the car, we just need to drive it, so hopefully I keep pushing that pedal."

Kim said securing his tour card the previous week in Detroit with a solo-seventh-placed finish had allowed him to freewheel a little at the Wyndham Championship, where he became the third South Korean winner of the event following KJ Choi in 2005 and Kim Si-woo in 2016. He is also the ninth South Korean to win on the PGA Tour.

"A hundred percent, it took so much pressure off," said Kim Joo-hyung. "I think that's why I was able to rebound so nicely. I think last week that back nine was a 9-under-par round as well, but it was tough. Just knowing that if I could play well that week, I could come in here just not worrying about have I secured my card and everything.

"I told myself just have fun, enjoy it, you've got your card already, just enjoy every single moment and don't get too intense. But this back nine was crazy, it was probably the most intense round I've played. My putter felt like 200 pounds today."

The 24-year-old Im was disappointed to fall short in his attempt to land a third PGA Tour win after he signed off with a 68.

However, finishing tied-second saw him finish 10th in the Comcast Business Tour Top 10 as he pocketed a $1 million bonus. He also took his hat off to Kim, who he played a practice round with at the start of the week.

"I missed a few clutch putts on the front nine which got me to a bad start, but overall I'm happy with the tie for second," said Im.

"I'm really, really happy for Tom. He's a great kid and to come out here and to win on tour as a nonmember and secure your card is really not an easy task and he achieved that. I'm really proud of him."