American snowboard legend Shaun White breathed a heavy sigh of relief after leaving it until his second and last run to qualify for the final of the halfpipe at the Beijing Olympics on Wednesday.

The three-time champion will retire from competition after the Games and the 35-year-old looked in danger of going out with a whimper after fluffing his first run, falling over and scoring just 24.25 to leave him a lowly 19th.

With only the top 12 going through to the final, he had to keep his nerve for his second effort, and he did just that, his 86.25 propelling him up to fourth and an ultimately comfortable passage into Friday's decider.

Japan's Ayumu Hirano topped qualifying with 93.25 at Genting Snow Park.

AFP