Aberdeen defender Mark Reynolds has been ruled out for the rest of the year after undergoing surgery on his knee.
The 31-year-old, who joined the Dons from Sheffield Wednesday on loan in 2012 before making the move permanent a year later, has made 237 appearances for the club.
Manager Derek McInnes said the news was a blow.
He said: “It’s extremely disappointing that our worst fears were confirmed last night when he went into surgery.
“We’re going to be without him for the next six or seven months so it’s a huge blow especially when these things happen in a pre-season game, but injuries are part and parcel of that.
“Knowing the character that Mark has, we’re hoping his rehabilitation will be as straight forward as possible.
“We’re disappointed for ourselves because we’re missing an important player, but we’re disappointed for Mark because he had worked extremely hard during the close season to give himself the best chance of being that important player he has always been for us.
“Unfortunately, he’s going to have to take a back seat now and work hard with the physios but I wouldn’t bet against him coming back as strong as ever.”