Lee Kyoung-hoon claimed his first PGA Tour trophy after winning the weather-hit AT&T Byron Nelson by three strokes, earning him a spot at the upcoming US PGA Championship.

South Korea's Lee weathered a storm on Sunday, fighting through heavy rain and a soaked golf course down the stretch to card a six-under-par 66.

Lee tallied eight birdies – including at the 17th and 18th holes to end the tournament – and two bogeys to celebrate his maiden title, while becoming the third South Korean golfer to win the event after Kang Sung-hoon (2019) and Bae Sang-moon (2013).

The 29-year-old will now feature at the US PGA Championship, which gets underway on May 20 in South Carolina, after finishing 25 under overall, ahead of overnight leader Sam Burns.

"It's been a long time for me and the conditions were very hard for everybody today, but I tried patiently and kept playing positively," said Lee, who is set to feature at his third major event – having missed the cut at the U.S. Open in 2014 and 2019.

"I have waited a long time for the win so I am very happy, very excited and very thankful for everybody. I still can't believe it but this time, I had more belief and my mind was stronger so it was perfect for me. I can't believe it I am so excited."

Burns, who was eyeing his second PGA Tour title in as many starts, carried a one-shot lead into the deciding day but a two-under-par 70 saw him finish outright second.

Patton Kizzire (63), Daniel Berger (64), Scott Stallings (66) and Charl Schwartzel (68) were tied for third, four strokes behind Lee.

Former world number one Jordan Spieth's final-round 71 was only enough to secure a share of ninth position at 18 under as he dropped nine places.

Masters champion Hideki Matsuyama (70) – playing for the first time since becoming the first Japanese man to win a major golf event last month – closed out the tournament 13 strokes adrift of Lee.

Meanwhile, big-hitting American star Bryson DeChambeau – the reigning U.S. Open champion – posted a bogey-free round (69) to move to 10 under, tied for 55th.