McElroy, ranked 25th in the world, clocked 51min 25sec to seal an impressive win in the South Korean city.

The American, second at the World Triathlon Series in Leeds last year, finished eight seconds clear of nearest challenger David Castro Fajardo of Spain.

Fajardo completed the course in 51:33 to take silver in front of McElroy's compatriot Kevin McDowell, third in 51:35.

"I feel great and tried to have fun today," said McElroy.

"As soon as I saw the TV, I knew I had a bit of a gap from fourth and that I had a podium. 

"As soon as I kicked it up on the hill, I cam flying down and just didn’t look back."

Sandra Dodet of France upgraded her silver from the corresponding event last year to gold as she won the women's race.

Dodet clocked 57:10 to beat Japan's Ai Ueda, second in 57:13.

Belgium's Claire Michel finished in 57:18 to earn the bronze medal.

"The bike was aggressive and I knew I had to be very powerful on the run because of the hills and because of the strong girls," Dodet said. 

"I gave everything today."