Olympic gold medallist Lindsey Vonn is out for the season after a crash on the opening day of the Alpine Skiing World Championships in Austria.
Vonn was airlifted to hospital after rupturing cruciate ligaments in her right knee but she should be back to defend her Games title at Sochi 2014.
The crash happened on Tuesday during the women's super-G event.
A helicopter was immediately called with medics treating the 28-year-old American on the slope for 12 minutes.
The United States ski team said Vonn tore her anterior and medial cruciate ligaments in her right knee and fractured a bone in her lower leg.
Lindsey Vonn factfile
Minnesota, United States, 18 October 1984
World Cup debut aged 16 in Park City, Utah
Competes at Winter Olympics in Utah aged 17 in downhill and combined
Claims first World Cup race win at Lake Louise in Canada
Wins first World Cup title to become only the second American woman to lift the trophy
Wins World Championships in Val-d'Isère, France, and becomes first American to win women's world Super-G title
Wins downhill gold at Winter Olympics
Loses World Cup overall title to friend Maria Riesch
Regains World Cup overall title. Request to compete in a men's World Cup downhill ski race rejected
Vonn, a four-times overall World Cup champion, was 0.12 seconds outside the time of race leader and eventual winner Tina Maze of Slovenia when she fell.
The 2009 world downhill and super-G champion appeared to land on the side of her ski after a jump and flipped over before crashing into a safety gate.
The race at Schladming, which had been delayed by three and a half hours because of fog, continued after Vonn was taken to a local hospital but Maria Hoefl-Riesch and Anna Fenninger also dropped out after mistakes on their runs.
Switzerland's Fabienne Suter, who finished fifth, described the problems with visibility on the run.
"It's not a very difficult course but in some parts you couldn't see anything," she said.
Maze won in a time of one minute, 35.39 seconds, with Britain's Chemmy Alcott 24th (1:38.18).
Vonn made her World Cup debut aged just 16 in 2000 before competing at the 2002 Winter Olympics in Utah. In 2008, she claimed her first World Cup title to become only the second American woman to lift the trophy.
The Minnesota-born skier went on to
secure gold in the downhill event at the Vancouver Winter Olympics in 2010
and also took bronze in the super-G.
Vonn's request to compete in a men's World Cup downhill ski race was
rejected by the International Ski Federation (FIS) last year.