Worthington and American great Hannah Roberts headlined a pulsating women's final on Sunday at Ariake Sports Park as Australian Natalya Diehm finished fifth.

First Roberts, the three-time world champion, appeared to cement the gold medal with a commanding opening run of 96.10.

Then Worthington, who crashed in her first run on Sunday, became the first woman to nail the 360 backflip in competition and unleashed a front flip for good measure.

That gave her the lead with 97.50 - the best score possible is 99.99.

Worthington's outrageous performance unexpectedly put the pressure back on Roberts and she conceded in the opening seconds of her one-minute run when the American great failed to execute a trick.

Roberts limped off the course as Worthington celebrated the gold medal.

The American took silver and Swiss Nikita Ducarroz won bronze with her first run of 89.20.

Diehm, who was fifth after Saturday's opening rounds, moved into bronze medal contention with her first run of 86.00.

But she could only managed 80.50 in her second run and slipped back two places.

Australian Associated Press