Massey did add two more tries in the second half but their lineout was starting to wobble and Takapuna Grammar's staunch defence came to the fore, while Koller kept applying the pressure in multiples of three. Leading the way in the pack was stringbean lock Tom Parkin and captain and hookier Lockie McNair, a converted loose forward.
Takapuna Grammar are back in action today against Westlake BHS, who thrashed Whangarei BHS 68-5, while Massey host Rangitoto, who beat Birkenhead 46-5. Rosmini defeated Orewa 43-3 on Saturday.
In Auckland 1A action, Sacred Heart retained the Fitzpatrick-Kirkpatrick in edging King's 13-12, the same one-point margin as in 2016. King's scored two tries - to wing Callum Douglas and lock Isaiah Mapusua - while fullback Josh Ka was the sole tryscorer for the visitors. The boot of first five Chay Fihaki, with three goals, was decisive, as was the Sacred Heart scrum.
MAGS, mentally and physically drained after their Sanix exertions, fell to a shock 20-15 defeat to surprise early leaders Dilworth.
Auckland Grammar were upset 24-19 by De La Salle but bounced back yesterday to take their traditional against New Plymouth BHS 28-0 in what is always a busy May.
There were victories for Kelston BHS (30-20 over Aorere) and St Peter's (15-0 over Tamaki), while St Kentigern clicked straight into gear, crushing Liston 95-0.
In the Hurricanes festival, the rampant style of Hastings BHS shows no signs of abating. They hammered St Pat's Town 106-7.
In the UC Championship, which is in the spotlight for what is perceived to be an unfair garnering of certain players by some schools, Christchurch BHS edged Timaru BHS 22-16 in the closest game on Tuesday, while on Saturday, Nelson made a fifth successful defence of the Moascar Cup in thrashing Burnside 74-7.
This Saturday's televised match is the 5pm curtainraiser to the Hurricanes v Cheetahs: Wellington College takes on Palmerston North BHS in a Hurricanes Tranzit Festival fixture.
North Harbour 1A
Takapuna Grammar 27 (Oscar Koller, Saki Rokolui tries; Koller con, 5 pen) Massey HS 22 (Anthony Naititi 2, Blessed Tumua, Miracle Naititi tries; Ryan McMillan con) HT: 15-12
Rosmini 43 Orewa 3
Westlake BHS 68 Whangarei BHS 5
Rangitoto 46 Birkenhead 5
Auckland 1A
De La Salle 24 Auckland Grammar 19
Dilworth 20 MAGS 15
Kelston BHS 30 Aorere 20
Sacred Heart 13 King's 12
St Kentigern 95 Liston 0
St Peter's 15 Tamaki 0
Traditional
Auckland Grammar 28 New Plymouth BHS 0
Auckland 1B
Tangaroa 20 Mt Roskill Grammar 15
St Paul's 28 Avondale 23
Botany Downs 41 Macleans 5
Otahuhu 29 Howick 13
One Tree Hill 32 Pakuranga 27
Onehunga 29 Edgewater 5
Papatoetoe 22 Southern Cross 17
Waitakere 30 Mangere 0
Chiefs Cup
St Paul's Collegiate 47 Manurewa HS 7
St John's (Hamilton) 13 Wesley 10
Hamilton BHS 42 Tauranga BC 5
Rotorua BHS 34 Francis Douglas Memorial 14
Chiefs Trophy
Hamilton BHS Second XV 57 Pukekohe HS 7
Western Heights 25 Rosehill 12
Cambridge HS 85 Wesley Second XV 0
St Peter's (Cambridge) 41 Taupo Nui-a-Tia 0
Chiefs Bowl
James Cook HS 41 Paeroa 27
Te Awamutu HS 65 Waiuku 7
Bay of Plenty
(Division one)
Opotiki 12 Te Wharekura o Mauao 68
Bethlehem 23 Aquinas 0
Rotorua BHS Third XV 25 Trident HS 10
Rotorua BHS Second XV 24 Tauranga BC Second XV 5
Hurricanes Festival
Gisborne BHS 34 Rongotai 7
Palmerston North BHS 44 Wairarapa 3
Hastings BHS 106 St Pat's (Town) 7
Napier BHS 15 Wellington 0
UC Championship
St Andrew's 15 Marlborough BC 0
Lincoln Combined 50 Aoraki Combined 5
Nelson 74 Burnside HS 7
Rangiora HS 28 Mid Canterbury Combined 11
Waimea Combined 40 St Thomas 29
Christ's College 41 St Bede's 19
Christchurch BHS 22 Timaru BHS 16
Otago
Waitaki Boys HS 34 Dunstan HS 17
John McGlashan beat Kavanagh by default
Otago BHS Second XV 22 South Otago HS 16
King's HS 54 Mt Aspiring 7
St Kevin's 43 Taieri 20