Dave Williams told the club site this morning though that Forster's knee has made slight progress since the weekend and the Blues have decided to hold off the surgery in case it recovers.
Williams feels that if the inury continues healing naturally, Forster could be in contention for involvemet against Leeds at the end of the month, he said: "Fozzie has had a scan and the specialist revealed there is no new evidence of a problem and is reluctant to operate at this stage.
"The new is improving. It's certainly better than last week and as long as he keeps moving forward surgery won't be necessay.
"He won't be available for Southampton but Leeds at the end of the month is a possibility. It depends on ho Fozie's progress goes from here."
He also outlined that should an operation be required, the former Reading man, who has already undergone surgery on the knee at the start of this season, would face one month on the sidelines.
In other injury news, Adam Proudlock, who also saw the knee specialist with Forster last week should return to first-team training by the end of this week.
Dave Williams told the club site that te former Sheffield Wednesday man has started running again since he suffered a reaction to his knee injury in a substitute appearance against Stoke.