Jimmy Thelin says he is “very disappointed” to be missing Dante Polvara for a “significant portion” of next season after the American suffered a hamstring injury in training.
The 24-year-old Polvara is expected to miss 14 to 16 weeks of action following the injury and will meet with a consultant soon.
The midfielder established himself as a first-choice starter in the latter stages of last season, making 40 appearances in the campaign and scoring four goals.
“We are clearly all very disappointed for Dante, especially as he made such a positive impression during pre-season,” said Aberdeen manager Thelin.
“He is an important player for us to lose at such an early stage of the season, but he will have the full support of everyone at the club and I am sure he will come back stronger from this setback.”