Antti Niemi will miss Saints' pre-season tour of Sweden after undergoing a knee operation.

The Finnish international is set to be sidelined for eight weeks following the surgery to correct the knee problem which affected him over the back end of last season.

Niemi, who is also ruled out of Finland's Euro 2004 qualifiers this month, should be fit for the start of the season.

Saints physio Jim Joyce, who interrupted his holiday to travel to Helsinki to see Niemi's scans which revealed ligament damage hadn't healed as well as was hoped, said: "I discussed it in detail with the surgeon and if we had not gone ahead there would have been a risk of him breaking down again.

"It made more sense to get it over and done with now so he had the operation in Helsinki.

"It is not a major reconstruction just the removal of some scar tissue and stitching together some torn tissue.

"It is not a common injury. I can only recall one player having something similar in my eight and a half years at the club and that was Christer Warren.

"Antti won't be fit for the tour, from 22 to 30 July, and obviously misses the two internationals in the next week.

"But he should be back in action well before the league season begins on August 16."

Niemi was already suffering from a torn calf which saw him stretchered off during the FA Cup final to be replaced by Paul Jones but it is unclear whether the knee injury played a part in that muscular tear.

The 30-year-old's surgery could also lead Jones to have a re-think as to his Saints future.

The Welsh number one has said that he needs to move away from St Mary's to get regular first team football to prolong his international career but with Niemi missing much of pre-season it could provide Jones with one last chance to stake his claim to Gordon Strachan.

However, when Niemi returns he will still be Strachan's first choice between the posts so it is likely Jones will still opt to leave Saints if he can find a move that is right for him.