Dunstan High School achieved the upset of the Highlanders First XV season when it beat Southland Boys' High School 31-10 in Alexandra on Saturday.
It was the second time in the four-year history of the competition that Dunstan had captured a major scalp.
The Central Otago school beat Otago Boys' High School in Alexandra two years ago.
This was the first time Dunstan had beaten Southland Boys'.
Dunstan has had some close losses this year but put its game together with a passionate display by backs and forwards.
Big lock Will Meehan scored a try and Callum Clark kicked three penalty goals to give Dunstan a 14-5 lead at the break.
The fleet-footed loose forwards dominated the breakdown and gained turnover ball that it used effectively.
The defence of the Dunstan team was a feature, and it stopped Southland Boys' from using its usual free-flowing game.
The Dunstan forwards displayed their dominance early in the second spell when they drove 15m after winning a lineout and blindside flanker Harry Paulin scored the try.
The other second-half tries were scored by hooker Ryan Fulton and winger Liam Mulvihill, who scored a runaway try after an intercept.
John McGlashan College retained the Tom Casey Cup when it beat Kavanagh College 27-0 in windy conditions at Kettle Park.
McGlashan led 15-0 at the break and defended vigorously when Kavanagh had the wind at its back in the second spell.
The two second-half breakouts led to tries.
McGlashan also scored two tries in the first spell and got the vital bonus point.
The best players for McGlashan were lock Braden Jane, who dominated the lineout and was mobile around the paddock, and fullback Chris O'Connell. No 8 Cameron Wood had a strong defensive game.
Centre Marckis Schaaf scored two tries and the other tries were scored by hooker Sam Pringle and winger Ben Grant.
Fullback Gavin Stark scored all three tries when South Otago beat Menzies College 17-0 in Balclutha.
The South Otago pack out-muscled Menzies and gained quick turnover ball.
The inside pairing of Dion Shaw and Caleb Edwards controlled play efficiently.
In the other game, Gore beat James Hargest 48-14.
