After missing Scotland’s victories against Australia and Costa Rica in April due to a knee injury, 33-year-old Aston Villa defender Corsie was anticipated to make a comeback.
However, due to an undisclosed injury, she is out and Celtic captain Clark, 29, who has four caps, steps in to fill her spot.
Scotland will play Northern Ireland live on BBC Scotland on Friday in Dundee.
Tuesday’s doubleheader between Scotland and Finland serves as practice for the inaugural UEFA Women’s Nations League, which begins in September.
The team of Pedro Martinez Losa, which was eliminated from this year’s Women’s World Cup after losing to Republic of Ireland in a play-off, is in the top category of the Nations League, where they are grouped with teams from England, the Netherlands, and Belgium.
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