Goals from Jeff Kenna have been a rare commodity during his career but he struck for the second time in a fortnight to complete a stirring Birmingham comeback against Gordon Strachan's side.
The former Republic of Ireland international had netted just once in eight and a half years before hitting the target against Manchester City on St Stephen's Day.
Then the 33-year-old, out of contract in the summer, popped up midway through the second half to exchange passes with Clinton Morrison before sliding the ball past Antti Niemi from close range.
To add to their misery David Prutton was dismissed for violent conduct immediately after that goal for appearing to elbow Kenna who needed stitches before being able to continue.
Southampton started brightly and Brett Ormerod - who replaced the axed Kevin Phillips - put them ahead after five minutes but the home side gradually established a grip on proceedings, and were duly rewarded 12 minutes later when Stephen Clemence's head met the recalled Bryan Hughes' deep corner and the ball flew into the corner of the net.
Bruce was full of praise for Kenna afterwards: "Jeff has been fantastic since I brought him back into the team and I couldn't have asked for anymore. He has showed what a top pro he is.
"I have told him that if we stay in the Premier League then there is no way that he is going to go anywhere. Where can I replace him?"
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