Kim stunned by 17-year-old Choi, Hämmerle wins back-to-back gold
South Korea's Choi Ga-on stunned top favourite Chloe Kim of the United States to take women's snowboard halfpipe gold on Thursday. On her opening run, Choi was left face-down in the middle of the pipe, where she was motionless for a moment while a stretcher was called.