The result moves Otago into third place in the ASB Premiership, two points behind Auckland and Waitakere which sit equal on 12 points.
Otago pounced into a second-minute lead when captain Tristan Prattley drove a free kick goalwards and, as a farewell present, Michael Cunningham hammered in the rebound, a 25m thunderbolt.
Cunningham and defender Tom Connor leave soon to try their luck in the Melbourne football scene, and both players were an integral part of Otago's fine win.
Cunningham was all class and poise on the ball while, as the game progressed, Connor roared forward on attacking runs that that should have clinched the match much earlier.
But if the Australia-bound players did well, they were probably outshone by Darren Overton and Prattley who did their chances of selection in the New Zealand Olympic squad no harm at all with consummate class in defence and attack.
Those four have starred all season for Otago and, while Cunningham and Connor will be missed, several other blue shirts showed courage and skill to blunt Canterbury and launch Otago forward.
Another fine performance by centreback Matt Joy nullified coach Keith Braithwaite's imported striker George Stefendorfas, whose frustration eventually erupted by launching an elbow at Prattley that earned a 75th-minute red card from referee Mirko Beneschke.
Referee Beneschke attracted criticism from both sets of supporters, with coach Braithwaite especially angry at some decisions.
Yet in what was clearly a tough physical derby match, Otago's youngsters emerged with honour. Morgan Day combined tight midfield skills with hard work and break -down tackles.
Harley Rodeka cranked up typically pacey runs, Ant Hancock battled on the ground and in the air to pull defenders adrift, and Regan Coldicott showed acceleration and finishing power, and was a whisker away from making the score 2-0 inside five minutes.
Hardly a youngster, left fullback Craig Ferguson did not miss a tackle, and his experience showed with some superbly flighted passes up the line.
Veteran goalkeeper Peter Evans hardly had to save a shot in anger, and capably fielded the few quality crosses that came his way.
However, the big keeper was tempted to show his dazzling footwork a couple of times, beating attackers on the ground which caused a communal cardiac gush among nervous Otago supporters.
Coach Murray also gave his bench a chance to show its worth, and academy youngster Joel Stevens' pace and tight control promises much, as did the glimpse of striker Donnie MacGregor, and Roslyn's young midfielder Sam Mepham who pounded a fine header off the Canterbury crossbar.
Canterbury coach Braithwaite admitted his side had just not played well: "It's a strange game. We went so well last week".
One of the few red shirts to register credit was the bustling import Darren White who carved forward on runs, but generally a nondescript match by Aaron Clapham, and one-dimensional route one tactics aimed at big striker Stefendorfas just did not pay off.
Otago United coach Richard Murray applauded his side's hard working ethic, which closed down Canterbury's options and, in a match that threatened to boil over, Otago did not shirk a tackle.
"The real contest now for Otago will be during midweek training as players vie to earn the gaps left by Cunningham and Connor," Murray said.
"It's a healthy situation and, with the huge task ahead of playing Auckland away next week, we will need to be firing on all cylinders."
THE SCORE:
• Otago United 1
Michael Cunningham 2
• Canterbury United 0
• Halftime: 1-0.
