Five-time Olympic medallist Bode Miller said the Rosa Khutor Sochi 2014 downhill piste "could kill you".
The American hit speeds of 82.4 miles per hour in final training but was shaken after seeing team-mate Marco Sullivan narrowly escape a crash.
Earlier, Slovenian Rok Perko also crashed heavily and was left with a bloody nose.
"If you are not totally focused and paying attention, this course can kill you," said 36-year-old Miller.
Miller topped the times in final downhill practice ahead of Sunday's race at 07:00 GMT, with rival Aksel Lund Svindal, the reigning world downhill champion, second.
Sullivan lost control on a flatter section soon after landing off the Bear's Brow jump and was heading towards a flimsy-looking red plastic safety fence at high speed before veering to safety and abandoning his run.
The slick 3,495-metre track caused havoc with 10 racers failing to finish in training ahead of the showpiece men's alpine skiing race.
"It's very treacherous," added Miller. "This course has teeth everywhere."
"The top is aggressive, speeds are so high and the turns are so swingy and bumpy that you can hook an edge anywhere.
"You saw Marco today. It doesn't look like it, it's an innocuous place and there's nothing there, but he almost killed himself. If that crash doesn't go just the way it went, he goes flying through B nets going 75 mph straight into the trees."
Miller, who won gold in the super-combined, silver in the super-G and bronze in the downhill at the Vancouver Games four years ago, clocked two minutes 06.09 seconds, 0.66 ahead of Svindal.
Italian duo Peter Fill and Werner Hill were next fastest down, at more than one second off Miller's electrifying pace.
Defending Olympic champion Didier Defago was in 10th 2.07secs adrift, with Swiss teammate Carlo Janka's recent return to form enough to see him finish fifth in training.