Alex Ainley scored a late try to give the Tasman a close 24-19 win over Waikato in Blenheim.
Trailing 19-16 with minutes remaining, Ainley dived over for the match winner after a great run by James Lowe got them close to the line.
Both sides exchanged early penalties before Jordan Trainor crossed for the game's opening try.
The Makos hit two penalty goals before the break, but the Mooloos still held the lead.
Tasman halfback Finlay Christie swept across for Tasman's first try, before the boot of Damian McKenzie tied things up heading into the final 10 minutes.
This was the Makos' fourth straight win over Waikato.
Tasman will face Canterbury, who were the best team in the first round of Mitre 10 Cup, while Waikato will defend the Ranfurly Shield against North Harbour, who beat Counties Manukau in their first game.
Newshub.