Chloe Kim dominates snowboard halfpipe to retain her Olympic gold

• Gigantic opening run ensures champion defends her title
• 21-year-old reaps benefit of time away from the slopes

American snowboarder Chloe Kim has become the first woman to successfully defend the Olympic halfpipe title, soaring to an untouchable lead with a gigantic opening run and cruising to a historic repeat gold.

Kim, dropping in last among the 12 competitors to qualify for Thursday morning's final, set the bar with a huge first run which included two 1080s and three spins down the course known as the Secret Garden Olympic Halfpipe, covering her mouth and dropping to her knees in jubilation upon seeing her score of 94.00 announced.