That was especially clear during a first half in which Wellington were allowed more than 70 per cent possession, seizing a 17-0 lead after only 15 minutes through tries from Hoani Matenga and Aumua.
But Northland tackled well and managed to make the most of their limited opportunities with ball in hand. First Peter Breen was denied due to a clear obstruction and then Solomona Alaimalo showed enough pace to scamper across the line after Wellington were caught short through a quick tap.
The Taniwha, though, were conceding too many penalties to cage the Lions for long, with the visitors continuing their stranglehold on possession in the second spell. And all the pressure eventually told, although Northland's cause certainly wasn't help when Kara Pryor was sent to the sin bin for a high shot on Shaun Treeby.
Wellington certainly found playing against 14 men to their liking and Aumua soon struck twice more, set up first by Sam Lousi's offload before finding himself in space on the right to complete his hat-trick.
Northland 21 (S. Alaimalo, M. Matich, S. Neville tries; P. Breen 3 cons)
Wellington 29 (H. Matenga, A. Aumua 3 tries; J. Garden-Bachop 3 cons, pen)
Halftime: 7-17