Fanny Smith sealed the women's ski cross Crystal Globe in style with an astonishing come-from-behind gold in Bakuriani, Georgia.
The Swiss was distant last in the closing stages but a late surge saw her overtake world champion Sandra Naeslund and take victory in a photo finish.
It was Smith's sixth World Cup gold of the season, and was enough to wrap up a third overall World Cup title.
GB's Atkin, 18, continues fine form with World Cup silver
"I had a really bad start," said the 28-year-old.
"And then I knew I was behind and I was just thinking to myself 'I am going to get them!' and then I went for it.
"It was a really nice final and all the girls fought really hard and I am so happy with this win today."
With two races left in the 2020-21 season, Smith leads the overall standings by nearly 300 points. Canadian Marielle Thompson sits second on 457 points, and was skied out of the medals in Georgia to finish fourth.
In the men's race, Canada's Reece Howden went out in the quarter-finals but still did enough to wrap up the Crystal Globe in his first full season on the circuit.
Howden's compatriot Jared Schmidt won gold on the day.
Atkin continues fine form with World Cup silver
Smith and Howden claim ski cross crystal globes