Jun, who competed for his nation at last year's Olympic Games, held off the challenge of compatriot Lee Ji-hun to finish at the top of the podium.

Patrick Dogue of Germany did enough for the bronze medal having been edged out for silver by Lee.

Jun, silver medallist at the World Junior Championships last year, secured his second title of the UIPM World Cup season with a total of 1,458 points - five more than his team-mate could muster.

Dogue was a further two points adrift as Pavlo Tymoshchenko of Ukraine, silver medallist at Rio 2016, was denied a fourth consecutive World Cup podium result.

"We showed great teamwork today and I'm very happy because we're having a great season," said Jun.

"In South Korea the pentathlon family now has many good athletes and the future is bright."

Lee gained the early advantage as he was the best performer in the fencing ranking round, but both Jun and Dogue ensured they did not lose too much ground.

Jun made his move in the swimming event, clocking the fastest time of 2min 00.01sec.

Italy's Matteo Cicinelli was his closest rival as he touched the wall in 2:00.72.

Cicinelli conceded just seven penalty points in the riding section of the event to make sure he kept pace with the South Korean athletes.

Ilya Palazkov of Belarus was also in with a chance of gold and started the concluding laser-run narrowly behind Lee.

The duo were locked in a close battle for the title until Palazkov made a crucial shooting error, allowing Jun to come through to wrap up an impressive win.

The event concludes with the mixed relay race tomorrow.