Kaikorai showed plenty of pluck and courage but Southern had that extra touch of class to claim a narrow win at Bishopscourt.
It was one of those miserable, cold and wet days at the waterlogged Kaikorai ground, and both sides were forced to adapt a low-risk style of play.
Kaikorai, struggling to make an impact on the premier competition, played with a strong wind in the first half and used it to good effect.
The forwards, led superbly by all-action openside flanker Adam Hill, dominated the tight exchanges and Willie Lawson kept it simple behind the scrum.
But all Kaikorai could take from the first spell was a penalty, and a late try to prop Warren Moffat gave Southern the edge at the break.
Halfback Joe Burford kicked two penalties to extend the Magpies' lead.
But Kaikorai finished strongly with an opportunistic try to replacement back Richard Cowley, and the home side could be proud of its effort.
Southern 11 (Warren Moffat try; Joe Burford 2 penalty goals), Kaikorai 8 (Richard Cowley try; Bevan Passmore penalty goal).
Half-time: Southern 5-3.
Referee: Todd Pullar.
