Sweden's Andre Myhrer won the men's Olympic slalom on Thursday at the age of 35, keeping his head while others were losing theirs as both his main rivals destroyed their chances with uncharacteristic mistakes.

Skiing in his fourth Games and cheered on by King Carl XVI Gustaf of Sweden, Myhrer won by 0.34 seconds from Ramon Zenhaeusern of Switzerland and by 0.67 from Michael Matt of Austria.

Pre-race favourite Marcel Hirscher dropped out following a bad mistake half-way through the first run that sent his skis flailing, while Norway's Henrik Kristoffersen blew his chance of victory after just a handful of turns on run two.

"I think if you win the gold medal at the Olympics, which has been a big goal of mine throughout my career, it's something not many athletes are able to do and this was my last chance. This tops everything," Myhrer said after improving on the bronze he won in Vancouver in 2010.

The contest had been thrown wide open by Hirscher's shock failure in his favourite event as he chased his third gold medal of the Games.

That seemed to open the door to his arch-rival Kristoffersen, who set the fastest time of the morning to lead Myhrer by 0.21 seconds, but he skiied out early on his second run as the Swede looked on from the foot of the course.

"I'm not disappointed. Better to have tried and failed than never to have tried at all," said the Norwegian, who after years of close rivalry with Hirscher must have wondered if his day had come at last.

Matt, brother of 2014 slalom champion Mario, put in the fastest second run at 50.66 seconds to move up nine places from 12th.

"My brother called me after the first run, which is always bad news as it means I’ve done badly. I made a mistake in the second run as well and thought I didn’t have a chance of the podium. That makes it all the more satisfying," he said.