Flanker Jason Kelly thrived in an outstanding forward performance as Harbour outplayed Alhambra-Union at Watson Park.
The Harbour forwards took charge in the difficult conditions and shut Alhambra-Union out of the game as they retained the Speights Challenge Shield and leapfrogged the North Ground team into second place.
Harbour was dominant with the wind in the first half, and almost equally so playing into it in the second spell.
The front row of Pieter van der Merwe, Peter Mirrieless and Ben Nolan shunted Alhambra-Union back in the scrums, the pack was effective as it used the pick-and-go time and again to gain territory, and Kelly, Eben Joubert and Brad Griffiths were an excellent loose trio.
Kelly and van der Merwe crashed over for tries in the first eight minutes and Alhambra-Union defended well to keep the half-time deficit to 10 points as Harbour battered away inside the opposition 22.
The game was made safe three minutes into the second spell when, from another pick-and-go, Kelly bashed over for his second try.
Van der Merwe had a fine debut and looks to be a potential member of the Otago squad, Mirrieless was an inspirational hooker and captain but all the forwards played well in what was a commanding performance.
The backs played a secondary role but centre Siaosi Folau had another fine game, breaking the line almost every time he had possession.
It was a reality check for Alhambra-Union which, for the first time in recent years, faced life without Matt Clutterbuck, its captain and outstanding flanker.
Lock Cowan Finch tried hard throughout and winger Karne Hesketh always looked likely when he had the ball in broken play but Harbour thoroughly deserved its maximum points.
Harbour 20 (Jason Kelly 2, Gareth McComb, Pieter van de Merwe tries), Alhambra-Union 0.
Half-time: Harbour 10-0.
Referee: Doug Rodgers.
