Reigning Olympic champion Red Gerard fell just short of the podium in the men's slopestyle final with a fourth-place finish.
Gerard, who won the event at the 2018 PyeongChang Games, was beaten out by Canada's Max Parrot for gold, China's Su Yiming for silver and Canada's Mark McMorris for bronze. It's the first time an American didn't win gold in the event, which debuted at the 2014 Sochi Games.
Gerard was in line for a bronze medal until McMorris knocked him out of a podium spot on his final run. McMorris needed to beat Gerard's score of 83.25 and did just that with an 88.53.
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McMorris now has three consecutive bronze medals in the event. Meanwhile, Parrot, who won slopestyle silver at the 2018 Games, has his first Olympic gold and Yiming, 17, has his first Olympic medal.
It was Gerard who actually had the best first run of any snowboarder in the final with an 83.25.
But Gerard dropped to third when Parrot scored a 90.96 on his second run and Yiming recorded an 88.70 on his second run as well. Gerard failed to top either of those marks, with a 71.86 on his second run and a 28.65 on his third run, before he was overtaken by McMorris for third place.
Fellow Americans Chris Corning (65.11 score) and Sean FitzSimons (29.61) finished sixth and 12th respectively.