Magnusson did everything right and won in Idre for the second year in a row. The margin of victory over Elvira Öberg, who had a miss, was a crushing 54 seconds.
Johanna Skottheim, Lima, finished third, 1.48 behind Magnusson and with two misses.
It was incredibly fun. It's almost a little comical that I shoot four zeros again this year. I've had a bit of trouble in the distance, mostly shot full in the sprint, says Anna Magnusson to SVT.
Anna Magnusson was part of taking eight podium places in the relay in the World Cup last season, but did not reach the podium individually. At best, she was fourth.
With Saturday's performance, it looks like Magnusson, who has a World Cup victory in her career, will be able to challenge the world elite in the World Cup premiere in Finnish Kontiolahti in two weeks.
The men complained about the icy track and the organizer had pisted the track before the women's race. They got better skiing conditions, but the wind made it difficult to shoot.
Elvira Öberg missed the first shot, but then shot 19 full hits in a row.
I had hoped for a bit more in the skiing, but it's still stable. I'm incredibly pleased, I miss the first shot and shoot full the rest. It's easy for uncertainty to come when you miss directly, says Öberg.
Her sister Hanna Öberg missed the premiere due to illness.
On Sunday, both women and men will compete in the sprint.
