(CNN) -- Lindsey Vonn's comeback to the World Cup skiing circuit was put on hold Friday as she faces a race against time to compete in the 2014 Sochi Winter Olympics.
The American superstar was set to return to competitive action at Beaver Creak next week, but suffered a major setback in training in Colorado Tuesday when she suffered a partial tear of one of her reconstructed knee ligaments.
"While her rehab is progressing, she is not at a point where she will be able to ski next week and is unfortunately withdrawing from the race at Beaver Creek," spokesman Lewis Kay said.
"She will continue to do therapy with an eye at racing in Lake Louise," he added.
That event takes place on the weekend of December 6-8 with two downhills and a giant slalom on the program.
Vonn, the reigning Olympic champion in downhill, is focused on defending her title in the Sochi Games which start on February 7, hoping to emulate the feat of compatriot Picabo Street at the 1998 Games in Nagano.
She suffered the original injury in a crashing fall at the world championships in Austria last February and has been receiving treatment from Colarodo-based orthopedic surgeon Bill Sterett.
"Lindsey is recovering very quickly from abrasions to her face and contusions to her shoulder blade," Sterett reported in comments released through Kay.
"Beyond that, she has a stable knee with an MRI finding of a partial tear of her ACL graft. With therapy, she is progressing well while not losing any of the strength she worked so hard to achieve."
The 29-year-old Vonn is a four-time overall World Cup champion and has won two golds at the world championship in a glittering career on the slopes.