Ester Ledecka shocked the alpine skiing world by winning the Winter Olympics super-G with a blistering run to upset the race favourites and deliver the Czech Republic a first gold medal in the sport.

The 22-year-old, who is among the favourites in the parallel giant slalom snowboarding, could barely believe it herself.

"How did that happen?" she said.

She tore up the bottom of the course to clock 1:21.11min.

That was enough to knock Anna Veith out of the gold medal position by one-hundredth of a second and deny the Austrian the chance to become the first woman to win back-to-back Olympic titles in the event.

"Surprised, completely, so is everyone, I think," said Italian Federica Brignone of Italy, who took bronze in the giant slalom on Friday and finished sixth in the super-G.

"She knows how to go fast when it's straight. She's great when it's straight and it's easy and not many turns."

Veith's time of 1:21.12 was enough for silver, while Liechtenstein's Tina Weirather claimed bronze in 1:21.22 after she had earlier edged Swiss Lara Gut off the top of the timesheets by the slenderest of margins in a thrilling race.

With the top contenders all going out in the top 15 positions, bib No.26 is the start position for a racer with only the slimmest chance of getting near the podium.

American Lindsey Vonn, who went out first but made a mistake before the final jump and finished sixth, was stunned along with the rest of her rivals.

"It's definitely shocking. In the Olympics a lot of weird things happen," said the 33-year-old.

Vonn will have another chance to become the oldest female medallist in Olympic alpine skiing in her favoured downhill on the same mountain next week.

-AAP