(Photo credit: Reuters/Aleksandra Szmigiel)

CORTINA D'AMPEZZO, Italy -- U.S. skier Lindsey Vonn's bid to win Olympic downhill gold with a ruptured ACL lasted less than 20 seconds on Sunday as the American great suffered a horrific crash early in her run.

Vonn, 41, whose battle to reach the starting line despite her knee injury dominated the opening days of the Milan Cortina Olympics, saw her unlikely bid end in agony.

Her teammate, Breezy Johnson, won the gold medal. Germany's Emma Aicher took the silver medal, 0.04 of a second slower, and Italy's home favorite Sofia Goggia won the bronze.

Johnson's Olympic title came exactly a year after she won world championship gold at Saalbach, Austria. She became the first American woman to win the Olympic downhill since Vonn did it in Vancouver in 2010.

On Sunday, Vonn appeared to clip the fourth gate with her shoulder and lost control, barrelling off the course at high speed before coming to rest in a crumpled heap.

Vonn could be heard screaming on television coverage as fans and teammates gasped in horror before a shocked hush fell on the finish area at the bottom of the Olimpia delle Tofane course.

She was surrounded by several medics and officials before a yellow helicopter arrived and she was winched off the course in an orange stretcher.

The helicopter took Vonn to Cortina's Codivilla Putti Hospital for a medical assessment.

Teammate Johnson covered her eyes and looked away as the helicopter was called.

As it took off toward Cortina, spectators applauded.

Vonn, the 2010 downhill champion, had been hoping to become the oldest Alpine skiing Olympic medalist after winning two World Cup races this year.

The American's crash sent shockwaves across day two of the Games.

Vonn's teammate, American downhill skier Bryce Bennett, watching in the town square in Bormio, was left shocked.

'It's obviously a bummer. It's just like the risk of downhill is high and ...like, everyone makes it look so easy when it's going smooth and then you see how quickly it can go in the other direction.

'Her right leg didn't look so good, but we'll see.'

There was no immediate word on Vonn's condition.

FIS president Johan Eliasch gave his thoughts on the crash.

'Tragic, but it's ski racing, right? And I can only say, thank you for what she has done for our sport because this race has been the talk of the Games and it's put our sport in the best possible light. I hope she will have a speedy recovery, and is back on skis very, very soon.

'A lot of people are going to say she shouldn't have been racing today with that type of injury.'

--Reuters, special to Field Level Media