New Zealand enjoyed a one-two in the men's triathlon with Hamish Carter taking gold.
Carter crossed the line in a time of one hour 51.07 minutes and was followed home by Bevan Docherty.
Switzerland's Sven Riederer finished in third ahead of a fast-finishing Greg Bennett of Australia.
Great Britain's Andrew Johns was well-placed after the 40km bike ride but fell back, eventually finishing 16th, with compatriot Tim Don 18th.
Team-mate Marc Jenkins earned a hero's welcome despite finishing last.
A collison midway through the cycling leg left the Welshman with a broken wheel.
But the 28-year-old put the bike on his shoulder and ran two kilometres to the next wheel station, finishing the race to applause from the British fans 15 minutes off the pace.
Winning triathlete Carter was delighted with his victory.
"I can't believe it - I've dreamed of it since I was eight years old," he told the BBC after the race.
"I felt I had him [Docherty], he was puffing a bit harder but I didn't want to under-estimate him. When I went I knew I had to go - he has a good finish."
World champion Docherty followed him over the line seven seconds back and was "super happy" with silver.
"It was a fantastic race. I didn't get gold, but what a person to lose to. I thought I had a chance but then all of a sudden the legs just went," he said.
Steve Potts of the United States emerged from the swim with an eight-second advantage, but that proved short-lived.
He was engulfed by the chasing pack in the opening stages of the first of five eight-kilometre laps on the challenging bike course.
The focus of each lap was the steep 700-metre 18-degree climb, and it was there that the field stretched and split on the third lap.
Six riders broke from a lead group of 15 and worked well together to maintain a healthy advantage going into the run.
Johns figured prominently along with the Kiwi duo, Swiss pair of Riderer and Olivier Marceau and Frederic Belaubre of France and they emerged from the transition with a 40-second lead.
The lead group then split again at the start of the run when Docherty, Carter and Riederer set a fast pace they maintained throughout.
As Bennett closed they upped the pace in the final stages, with first Riederer and then Doherty falling back to leave the way clear for Carter to claim a memorable win.
Johns, who had described himself as being in the best form of his life prior to the event, fell off the pace dramatically after the exertions on the 40km bike ride.
He trailed in three minutes and eight seconds down on Carter with Don coming in just behind.
"I put my cards on the bike and went pretty hard. When I got to the run I had spent all my biscuits, but that's the way it goes," a phlegmatic Johns said.
"The bike killed me and I had nothing on the run."