New Zealand's Sydney-born Zoi Sadowski-Synnott has narrowly missed out on a second gold medal at the Beijing Winter Olympic Games.

Anna Gasser of Austria executed a massive cab 1260 on her final jump to overtake Sadowski-Synnott and win her second straight Olympic gold medal in women's snowboarding big air.

Gasser, 30, held off a field with an average age of 21, including the 20-year-old Sadowski-Synnott, who last week won her country's first Winter Olympics gold medal in slopestyle.

Australia's Tess Coady, who won bronze in the slopestyle, finished ninth, despite a strong first run of 85.00.

Coady crashed out in both her second and third runs, to fall out of medal contention.

"First run was really good, a front 10, I didn't get one of those in practice so I was super happy to land that first run there," Coady said, smiling despite the disappointment of missing a medal.

"Second and third run, I tried a back 10, I've never done that one in comp before – got super close to it on my second run and then then third run fully missed the snap and under rotated pretty hard, all good."

Coady said this was "just a bonus" competition for her after nailing her priority competition, the slopestyle, earlier in the Games.

"I haven't done a whole lot of big airs in my career … it was really just a bonus to be doing this and then to make finals as well, that was sort of the approach I was taking the whole time.

"I was gonna have to send it any way so I just had a crack, it was good."

Coady was just as enthusiastic about the Big Air Shougang venue, the world's first permanent big air structure that is housed in the grounds of an old steel mill, through its rusting infrastructure crowds are guided through to reach the towering complex.

"A lot of the city big airs really suck," Coady said.

"They're really sketchy and people get hurt a lot of the time but this set up is incredible.

"The jump's really good to ride, the snow's been really good this whole time, and the landing's really long, and it makes such a big difference, we wouldn't have had such a good showing today if it wasn't such a good jump. I'll be looking forward to coming back and competing here."

Coady was just as enthusiastic about the history of the venue and how the use of the brownfield site could be a blueprint for the construction of other venues.

"I didn't know until a couple of days ago … that it was a refurbished steel mill and they did that to reduce pollution and stuff like that," she said.

"It's all made out of recycled materials and stuff like that which is really cool especially for a sport like snowboarding where people are promoting environmental sustainability.

"I absolutely think they should be doing more things like this because it's so great, aside from snowboarding it's a really good thing that people should be doing."

Sadowski-Synnott led Gasser by 0.25 points entering the third round after both landed a pair of double cork 1080s — two off-axis flips with three rotations.

Gasser was assured of silver when she dropped in switch for her final attempt at Big Air Shougang.

She was the first woman to land a cab double cork 1260 in competition when she did it 2019, and she did it again here, the only rider to stomp out a trick with three-and-a-half spins.

Sadowski-Synnott tried to follow with her own 1260, but couldn't hit the landing.

With her big air bronze from 2018, Sadowski-Synnott became the seventh snowboarder with three Olympic medals, a list that includes Shaun White and Jamie Anderson.

Kokomo Murase of Japan earned bronze, with a pair of 1080s. It was the first Olympic medal for the 17-year-old.

Sadowski-Synnott came out of the gate with the best trick of the first round, a perfectly executed frontside double cork 1080 — two off-axis flips with three rotations — that scored her a 93.25.

Gasser was second, at 90 points, after doing the same trick.

The Kiwi followed with a backside double cork 1080, which she landed clean for 83.75 points and the top spot entering the final round — 0.25 ahead of Gasser.

Coady, now at the end of her second Olympics but the first in which she has actually competed after the heart-breaking injury she suffered in PyeongChang, has had a hugely successful Games, something she puts down to hard work.

"Making two finals is so big for me, so incredibly stoked about that and I'm incredibly keen, once I've reset a little bit, to get back into it and just keep working hard because I just love progressing in the sport.

"It's so exciting to watch yourself progress and try new tricks and scare yourself."

Before that though, a celebration.

ABC/AP