The 31-year-old World No.138 closed with a four-under 67 to finish at 23 under and win the Byron Nelson tournament in Dallas by two stokes from Americans Matt Every (66) and Scott Piercy (64) on Sunday.

World No.3 Brooks Koepka showed he was primed for this week's US PGA Championship title defence as he finished fourth at 20 under after a closing 65.

Sydneysider Matt Jones produced his best result of the season as he tied for fifth, six shots behind Kang, after shooting 65-67 over the last two rounds.

RIGHT: Jones recorded his best result of the 2019 season, finishing T5th. PHOTO: Stuart Franklin/Getty Images.

Most players had to complete their third rounds before tackling the final round on a marathon final day.

Kang had to play 27 holes and said he decided to just relax and have fun despite a lack of sleep.

"Yesterday we finished too late and I didn't get enough time to sleep. I only slept about three hours," he said.

"When my turn came up I tried to really focus on it and it worked out great. I am so happy right now."

The success is indicative of the rise of South Koreans on the US tour.

In 2003, K.J. Choi was the only South Korean-born player and now there are 15.