Before the season, midfielder Andreas Murbeck was brought in from Landskrona Bois.
He was present from the start when Sirius rehearsed against IK Brage on Saturday.
Then the accident occurred.
He suffered a knee injury that now needs surgery and the recovery means that he misses the entire season.
- This message took hard and I am very disappointed to miss the coming season.
I have received extremely good support from everyone in Sirius and they are really warm.
Now I look ahead and will set clear goals to come back stronger, says the 23-year-old to the club's site.
Murbeck will undergo surgery in the near future, Sirius announces.
The Uppsala club will play an Allsvenskan premiere against Sundsvall on Sunday.