Cameron Brown and Joanna Lawn provided the kiwi double with both winning the inaugural Ironman 70.3 Korea triathlon on the island of Jeju yesterday.

Brown overcame a demanding course and the heat to go clear on the run, finishing comfortably ahead of fellow New Zealanders Guy Crawford and Kieran Doe in the all kiwi podium.

Lawn had an equally impressive day and was never threatened to win her third straight Ironman 70.3 international following wins at Port Macquarie and Busselton recently.

With the full Ironman race run in conjunction, Brown and the other 70.3 athletes had a later start. He trailed Doe and Crawford by just over a minute out of the 2km swim but caught them by the first lap turn with the trio riding together over the rolling hills.

Brown led on to the run and pulled away up the challenging 2km hill before opening a four minute advantage at the run turn at the national football stadium. He stretched out his advantage on the final 10km uphill to win in 4:03:58 with 12 minutes back to Crawford who just held off Doe for second.

"That was a really tough day with both the course and the heat. But after being sidelined for a few weeks with a calf injury I was really happy with how the run went and the race overall, considering I've done no speed work at all," Brown said.

"It's given me plenty of confidence now looking ahead to Ironman Europe Championships in Germany in three weeks time."

Lawn was never threatened today which became more a question of the quality of her performance than any danger with the victory.

The six time Ironman New Zealand champion was fifth out of the water overall behind the three kiwi men and Sweden's Fredrik Croneborg who won Ironman 70.3 China recently.

She maintained her position with a strong ride over the 90km course to finish only 16 minutes behind the leading men in seventh overall

Lawn won in 4:39:15 to be only 25 minutes behind Brown in an impressive performance.

She also heads to Germany tomorrow with Brown to prepare for the European race where they both hope to secure sufficient qualifying points to secure their places in October's Ironman World Championship in Hawaii.

Meanwhile Auckland's Bevan McKinnon finished third in the gruelling Ironman Korea with a time of 9:03.25 to cement an outstanding day for the New Zealand triathletes.

Ironman 70.3 Korea Provisional Results

Elite Men

1. Cameron Brown (NZL) 4:03:58
2. Guy Crawford (NZL) 4:15:03
3. Kieran Doe (NZL) 4:15:56

Women

1. Joanna Lawn (NZL) 4:38.54
2. Yasuko Miyaki (JPN) 5:12.38
3. Sarah Wheeler (AUS) 5:23.15