Alex Hall was victorious in Mammoth thanks in large part to his precision on the rails ©Getty Images

Alex Hall and Kelly Sildaru earned slopestyle victories at the Freeski World Cup stop in Mammoth, a first World Cup win since 2019 in Hall's case.

The American led men's qualifying at the Californian resort, meaning he skied last, and a stellar second run lifted Hall into an unassailable lead.

Hall scored 95.50 - impressing particularly on the third rail - to edge out compatriot and two-time Olympic medallist Nick Goepper.

Goepper amassed 94.75 points in second place, with Canada's Evan McEachran completing the podium on 93.00.

Nineteen-year-old Sildaru made it two wins from two in women's slopestyle events this World Cup season.

A score of 93.75 was just reward for a smooth first run in the final, and it proved a winning score.

The Estonian, who is a four-time Winter X Games slopestyle champion and the reigning Youth Olympic Games gold medallist in the discipline, won the season's only previous slopestyle event in Stubai.

Eileen Gu, China's reigning world champion, was second on 91.00 and American Maggie Voison third, scoring 90.00 on her second run.

Gu is 18 and there were three teenagers in the top four, as top qualifier Olivia Asselin from Canada placed fourth with a score of 89.00.