Andri Ragettli won his first World Championship gold medal, while Great Britain's James Woods was denied a podium place on the final run of the men's ski slopestyle event in Aspen.
Ragettli has won slopestyle gold seven times on the World Cup circuit but the 22-year-old recorded the biggest triumph of his career to date with a brilliant final run - scoring 90.65 points to snatch gold away from USA's Colby Stevenson.
Stevenson's second-run score of 89.55 looked set to see him climb the top step of the podium until Ragettli leapfrogged him at the last to win Switzerland's second gold of the Freestyle Ski and Snowboarding World Championships, following Alex Fiva's success in the ski cross last month.
GB's Atkin, 18, continues fine form with World Cup silver
The battle for third was equally as intense, with Woods' first-run score of 84.76 enough for him to be sitting in bronze medal position - behind Stevenson and Ragettli - heading into the last run.
But Alexander Hall laid down a score of 86.01 to snatch a podium place away from the Brit, with Woods ending the day in fourth after failing to improve on his own score third time around.
Atkin continues fine form with World Cup silver
Smith and Howden claim ski cross crystal globes