However the 18-year had to come from a two minute deficit after the kayak, behind the then leader - Sam Clark also from Whakatane, who finished fourth in 2h 45m 58s.
"It's such an unbelievable result for me. I can't even explain it and that's why I was so emotional crossing over the line," said Wilde.
"One athlete I was really watching out for was Sam. He's been my idol for years and it's awesome to beat him. He's such an amazing athlete.
"I was really pleased with my bike. I had to push myself to try and catch him when he had a that lead. I had to concentrate and get my levels down and wait until I could attack.
"And finally on one of the hills I just went for it. I'm just stoked to do so well because I have been focused on triathlon recently."
After finishing the course Wilde was congratulated by proud parents Sarah Wilde-Ennis and step dad James Ennis who were also very emotional.
"Words can't describe his achievement. We are just both over the moon for him," said mum Sarah.
"It was a very tough field today and Hayden really had to battle back. It's a very proud day for our family."
Wilde went into the course on the back of winning the 2016 full Nugget solo event in Waihi in May. And finishing first in the two day coast-to-coast World Multi-sport Championships individual race on the South Island in February.
"I've really increased my training recently and it's great that things are paying off," he said.
"Even though I have done well recently I didn't expect to get the win because of the quality of competitors.
"I was most happy with my bike section and I will be looking to work on my start to the race as I don't want that to cost me in the future."
Despite Wilde's success in multisport events the 18-year-old has hinted that his future lies in triathlon and he plans to put his promising multisport career on the backburner to try and get to the 2020 Tokyo Olympics.
"I've always wanted to go to the Olympics - it's the highest level of competition, so it would be such a great experience," he said.
" I'll not be doing much multisport in the years to come because my focus will be turned to triathlon.
"Hopefully I can make the Olympics because to represent my country would be such an achievement." he said.
The top finisher in the female field was Simone Maier from Wanaka in a time of 3h 09m 48s with Elina Ussher from Nelson finishing in second place with 3h 15m 01s and third spot going to Corrinne Smit in 3h 19m 46s.
For all the results visit www.thetimingteam.co.nz