Harbour showed just how devastating it can be when its gets its running game going.
The Hawks have scored more tries than any other team in the tournament, with 51. They scored 11 of those in the weekend against an under-strength Southern team.
University was just as dominant, romping to a 47-0 win against an Alhambra-Union side which had shown signs of improvement in recent weeks.
Highlanders trio Fletcher Smith, Josh Dickson and Matt Faddes made an enormous difference for the students. Faddes bagged three tries, Dickson dominated the lineouts and Smith showed his class at first five-eighth.
The more familiar they become with the team's structures, the more impact they will have and that should send a shudder through the rest of the competition.
University and Harbour are clearly the two form teams, and will slug it out at the University of Otago Oval tomorrow.
Potentially it is a preview of the final. Harbour, though, made a poor start to the tournament, and despite playing some sparkling rugby in the past month could drop out of the top four with a loss to University.
Taieri is other team to watch. It quietly beat Dunedin 29-18 at Peter Johnstone Park on the weekend and is keeping pace with University at the top of the standings.
The Eels trail University by five points but have a game in hand. Fullback Josh Casey produced a performance worthy of his 50th game.
He netted three tries, set up another and is the competition's leading scorer with 104 points. His haul, though, is still a long way off the all time season record of 300 points he set in 2015.
Taieri should be too strong for Green Island at Miller Park, but the home side is a much more competitive side than its position of seventh suggests.
It is running out of opportunities to push its way into the top four, so it will not lack for motivation.
The clash between Dunedin and Kaikorai shapes as another interesting encounter. Kaikorai found form last weekend with a comprehensive 59-6 win against Zingari-Richmond.
The Colours have fallen away in the past month and Dunedin will present sterner opposition.
But the Sharks have been up and down and have often struggled against Kaikorai. They did win the round one fixture 37-32, though.
Southern has the most to lose. It could drop as low as fifth if it trips up against Zingari at Montecillo.
The defending champion was depleted last weekend, when a host of regular starters were unavailable, including the competition's leading try scorer Josh Gordon.
The Magpies will, no doubt, have worked hard on their defence after haemorrhaging far too many points against the Hawks.