Lindsey Vonn has re-injured her surgically repaired right anterior cruciate ligament after suffering another crash in training as she prepared to make her return to competitive skiing.
The American, who had not raced competitively since tearing knee ligaments in her right leg in February, crashed during a training session at Copper Mountain in Colorado.
She was taken from the site on a sled but was not hospitalised.
It was later revealed the 29-year-old suffered numerous injuries, the most notable of which was a partial tear to her right ACL, which places her participation at next year's Winter Olympics in doubt.
"Lindsey Vonn sustained a mild strain to her right knee, a partial tear to her right ACL, minor facial abrasions and scapular contusions as a result of a downhill training fall Tuesday on the U.S. Ski Team Speed Center at Copper Mountain," said a statement on http://www.usskiteam.com.
"Vonn plans to rest for a few days before pursuing physical therapy.
"U.S. Ski Team Medical Director Kyle Wilkens reported her response to the therapy would ultimately determine the timetable for her return to active training."
The reigning Olympic women's downhill gold medallist started training again in September after seven months out of action following a crash at the first race of the 2013 World Championships in Schladming, Austria.