Iron attacker Gary McSheffrey has undergone surgery on a knee injury.
The problem ruled him out of last Saturday's away FA Cup clash at Leyton Orient, and manager Mark Robins explained more about the injury in his Tuesday press conference."He had the surgery on Tuesday and will be out for a while," explained Robins.
"He's had an issue for the last two or three years, which has just flared up, and we've decided that the time was right to operate."
Robins was reluctant to put a timescale on McSheffrey's recovery.
He added: "People respond and recover at different rates - it's not the same for everybody. Some get back a week or two earlier than others.
"We have to be mindful of factors such as age, and I am in the hands of the experts."
While he is unlikely to make this weekend's away game at Port Vale, Robins added defender David Mirfin is getting close to a return from a hamstring injury picked up in the game at Bury.
"He was in the team for a lot of our good games this season and has been a miss for us," explained the boss.
"We need him, and everybody, back fit and firing as quick as we possibly can."
Tweets by @SUFCOfficial