Cai took a dramatic victory in the women's event as she landed a leading 80.50 points on her third and final run to steal the win away from Japan's Sena Tomita.

Tomita flew out of the blocks with a 76.00 on her first run but followed it up with two lacklustre performances, to amass 34.25 and 33.25 points.

Spaniard Queralt Castellet rounded out the podium after posting a score of 70.50 points on her third run.

The win meant that Cai received 1000.00 FIS points while Tomita and Castellet earned 826.52 and 690.75, respectively.

Japanese 19-year-old Hirano set a remarkable score of 89.25 in the men's competition, which was enough to hold off strong challenges from the rest of the field.

Switzerland's Jan Scherrer earned 88.50 points on his final attempt to fly up the leaderboard and take the silver medal after recording scores of 23.75 and 17.25 in his first two tries.

Hirano's compatriot Yuto Totsuka made up the top three with 87.25 points.

Athletes will return to Copper Mountain in Colorado for the next FIS snowboard halfpipe event which takes place at the resort from December 9 to 11.