Kamo High School proved tougher competition than Whangarei Boys' High School expected in their Northland Secondary Schools league semifinal.
Kamo, who were in a lower division at the nationals, were level 10-10 at halftime on Wednesday before the competition favourites put their foot down in the second spell.
Boys' High made changes at the break and dominated the second spell, winning 40-28. In next week's final they face Okaihau, who beat Bay of Islands College 26-12 .
WBHS coach Craig Bird was full of admiration for his side's opposition.
"Kamo have a young and talented team and full praise to them - they brought their A game today and really matched us in that first half," he said.