His second run, a frontside 1440 with a tail grab, received 62.75 points, and the frontside 1800 tail grab on the third failed, but the 17-year-old was lucky to finish fifth, 155.25 points, to qualify for Tuesday's final.

"Firstly, I'm so happy that I've made it to the finals. Actually, I'm comparing today's game to the finals, since everybody is trying their best, I need to do some difficult tricks to get the qualification," Su said.

"I'll try to find out my technical issues tonight and hopefully I will finish all tricks I wanna perform tomorrow."

Veteran snowboarder Staale Sandbech of Norway, who's competing at his fourth and last Winter Olympics, failed to qualify for the final.