Canadian Olympic ski cross gold medallist Marielle Thompson sustained a serious knee injury while training in Switzerland this week, Alpine Canada said Friday.

The 25-year-old from Whistler, B.C., who won the gold medal at the Sochi Games in 2014, ruptured her anterior cruciate ligament (ACL) and medial collateral ligament (MCL) during a fall while training in Saas Fee for a pre-season preparation camp.

Alpine Canada said Thompson flew back to Canada for further assessment where an MRI confirmed the injury.

"It's definitely disappointing to hear the results of the MRI after such a productive summer of training in the gym and on snow," Thompson said in Alpine Canada's release. "I'll be making a plan with my team moving forward and when the time is right getting back on the ski cross course stronger than ever."

The ski cross World Cup season begins in December.