Wes Brown has been told that he is likely to be out of action for eight weeks with a knee injury.
The Sunderland defender sustained the injury during Sunday's 1-1 FA Cup draw with Middlesbrough and it was suggested that he could be absent for the remainder of the season.
However, manager Martin O'Neill has claimed that the injury was not as bad as first feared.
The former Aston Villa boss said: "We don't think he needs the operation, but he will be two weeks in a brace, two weeks elsewhere and you are looking at probably about eight weeks before he is back.
"But at one stage, it looked like a season-ending injury."
Sunderland are currently eighth in the Premier League.