TOKYO, July 26 -- Norway's Kristian Blummenfelt, the man they said didn't like the heat, delivered a devastating late surge to track down and break clear of a pair of relative youngsters Monday, surviving a sweltering run leg to take the gold medal in a thrilling Olympic Men's Triathlon.

Blummenfelt, 27, was part of a huge group of almost 40 that came off the 40km bike leg together but looked anything but a favorite among some young speedsters.

However, he kept driving at the front as the group was whittled down to three, before surging clear in the final kilometer to finish in one hour, 45 minutes and 4 seconds to take Norway's first medal in the sport.

Alex Yee, 23, continued Great Britain's impressive historical form, as his silver made GB the most successful nation in the history of the sport, which joined the Olympic program in 2000.

Fellow-23-year-old Hayden Wilde of New Zealand also ran strongly to take bronze, while Briton Jonny Brownlee, who won silver in 2016 and bronze in 2012 (and was hoping to complete the set in the absence his double champion brother Alistair), could not quite hang on and finished fifth.

The race began with an unprecedented and embarrassing false start, as a media boat drifted in front of the pontoon at just the wrong moment, blocking the route of around a third of the 56-man field as the rest dived in. Jetski riders eventually hauled a dozen back after they pounded out around 200 meters, oblivious to the alarm horns and whistles.

The field got away cleanly at the second attempt, and all of the expected frontrunners were in touch coming out of the water after the 1500m swim.

A group of 10 broke away for the first few laps of the 40km bike leg, but the chasing pack eventually reeled them in to form a giant group of 37 by the end of the fifth of eight laps.

All the main contenders were in there, and as was widely predicted, it came down to one big run showdown.

Pushing the pace in the heat the group slimmed down to three but it was the vastly experienced 27-year-old Blummenfelt, who is the world record holder for the half-Ironman triathlon distance, who had the strength to break clear.

Wilde summed up the great spirit among the athletes, taking the time to help haul Blummenfelt off the ground after the finish, and the two exhausted athletes stumbled away together..

The women's race takes place on Tuesday.

Reporting by Mitch Phillips, editing by Toby Davis and Michael Perry.