Korsgren has had a strong start to the season with empty podium places, second, first, first.
Results that means that before this weekend's competition she leads the cup with 670 points - 120 points ahead of second place Emilie Fleten.
The women's class does not start until tomorrow's race.
- Then we get to see where the guys catch up with us, they start ten minutes after us, and depending on where they get in the race, I think there can be some decisive moments there, says Korsgren.
"Extra nervous"
Britta Johansson Norgren has won the long-distance race Ski Classics five years in a row and last year she won the Czech sub-competition Jizerská.
After missing two races, due to the cold injuries she suffered during the premiere in La Diagonela in January, Johansson Norgren is now ready for a comeback.
- It feels like the season is starting again and I am a little extra nervous and do not really know how I will stand up to the others, but it feels great, says Britta Johansson Norgren to SVT Sport.