In Saturday's league match, the national team player slipped and sustained an injury.
On Sunday afternoon, an update came from the club.
The follow-up examinations showed a muscle injury near the hip joint on the left thigh.
A rehab period of at least eight weeks is to be expected ", the club writes in a statement.
Forsberg has accounted for six goals and two assists in a total of 25 matches for his German club team this season.
Fortunately for national team captain Janne Andersson, Forsberg is expected to be back when Sweden play the playoffs for the World Cup at the end of March.
Sweden meets the Czech Republic in the first playoff match on March 24.