Alsing went on the injury during training this week.
As a result, he looks to miss the rest of the basic series and if he is gone for eight weeks he is back only at the end of a possible quarterfinals series.
Alsing, 23, has received a huge lift this season and has debuted in Tre Kronor. He is the team's top scorer with 20 points (4 + 16) in 36 games.
He is loaned by Ottawa this season and should Djurgården miss the quarterfinals in the finals, his Djurgård career could be over.
Djurgården has shown good form lately and is currently on a quarterfinals place in the SHL table.