"I feel like I was riding well in training. I had to balance two tricks this time. So I had the switch back 16 and then the frontside triple 14 which was going to be the second trick.
"There was a lot of going on. I hadn't done that trick, the frontside 14, many times. So it was taking a lot of energy."
Despite the disappointing performance, Garcia Knight said he was proud of New Zealand's Winter Olympic games and thanked everyone back home for their support.
"I'm not super excited with how it all went but I'm so proud with our Winter Olympics. It's been huge.
"Everyone back home has been sending me so much love and to hear that alone is worth it enough. To have everyone back home excited is awesome. I can't even express that enough.
"I'm so excited for the next one already. I would've thought after the Olympics I would've been burnt out and over it but far out it's the complete opposite. That's pretty exciting on its own."
Canadian Sebastien Toutant claimed the gold medal after racking up a combined score 174.25.
Toutant edged out American Kyle Mack and Britain's Billy Morgan who earned the silver and bronze medals respectively.
Garcia Knight ended up in 11th place.
The Kiwi snowboarding star also came agonisingly close to a medal in the men's snowboard slopestyle, where he finished fifth.
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