Harbour attacked from all parts of the paddock in the last 20 minutes and almost caught Dunedin, who ran out victors 32-27.
Dunedin was hamstrung by the removal of the scrum in its 20-22 loss to Taieri at Forsyth Barr Stadium.
Dunedin hung on desperately in the final minutes to beat Alhambra-Union at Kettle Park.
Flanker Jack Wolfreys' speed to the breakdown and his support play played a key role in University A's win over Dunedin at Kettle Park.
Dunedin gave a clinical display of power and precision rugby to beat Southern 37-15 at Bathgate Park to win the Ron Reggett Memorial Trophy.
The aggressive play of No 8 Mark Atkins helped Dunedin to a convincing seven-try win at Kettle Park.
The Dunedin forwards got on top in the second spell at Bishopscourt, when experienced prop Kelsey Miller came on to the paddock and settled the scrum.
The powerhouse scrum, which took three tightheads, was the foundation for Dunedin's eight-try win over Pirates at Hancock Park.
It was men against boys as the powerhouse Dunedin pack dominated from the start and laid the platform for the win over Harbour at Watson Park.
Peter Breen deserved to kick the winning penalty because he was the best player on the paddock when Alhambra-Union beat Dunedin at the North Ground.
A rampaging Pirates pack blitzed a limp Dunedin team to retain the Larry Salmon Memorial Trophy at Kettle Park.
A committed Kaikorai team shut Dunedin out of the game when it gained an upset win at Bishopscourt.
Liam Edwards was the inspiration for an enterprising Dunedin team that scored six tries and retained the Centennial Trophy against Alhambra-Union at Kettle Park.
Prop David Smart gave an aggressive display and played a key role in Dunedin's 44-17 win over Green Island at Miller Park.
Replacement flanker Eben Joubert scored a controversial late try to give Harbour an upset 31-29 win over Dunedin at Kettle Park.
No 8 Andrew Stead was in dominant form and scored two of the six tries when Southern beat Dunedin 36-17 at Bathgate Park.
Dunedin came to life in the second spell to win an error-ridden game 42-12 at Kettle Park.
Taieri held on to beat Dunedin at Peter Johnstone Park despite a strong rearguard action by Dunedin in the second spell.
Two late tries exaggerated the winning margin when Alhambra-Union beat Dunedin at the North Ground.
The Dunedin forwards took control in the second spell to beat University A 34-19 at the University Oval.