A hat-trick from Bryce Heem helped Auckland beat Counties Manukau 31-16 in Pukekohe on Saturday.
The victory crucially books them a home semi-final.
Former Tasman man Heem opened his account in the fourteenth minute at ECOLight Stadium but a response from Counties Manukau number eight Maama Vaipulu meant the home side went in at the break 5-8 in front.
Despite the powerful Vaipulu crossing again in the 48th minute for the Steelers, Auckland went up the gears in the second period with penalties from Simon and Jono Hickey going with Heem's second on 54 minutes.
Strong finisher Heem would add the gloss in the 80th minute with his hat-trick and Auckland's final try of the game as they finish above Tasman, who they will host next week at Eden Park, in second spot in the league.
Tries: Vaipulu 2
Pen: Francis 2
Tries: Heem 3
Con: S Hickey, J Hickey
Pen: S Hickey, J Hickey 3
Counties Manukau: 15 Toni Pulu, 14 Frank Halai, 13 Sam Vaka, 12 Cardiff Vaega, 11 Sione Fifta, 10 Piers Francis, 9 Richard Judd, 8 Maama Vaipulu, 7 Sam Henwood, 6 Jordan Taufua, 5 Sikeli Nabou, 4 Jimmy Tupou, 3 Sam Aiono, 2 Gafatasi Su'a, 1 Pauliasi Manu.
Replacements: 16 Sione Anga'aelangi, 17 Sean Bagshaw, 18 Jarrod Firth, 19 Viliame Rarasea, 20 Onosai'i Auva'a, 21 Pele Cowley, 22 Willie Walker, 23 Jonathan Faauli.
Auckland: 15 Melani Nanai, 14 Bryce Heem, 13 Charles Piutau, 12 George Moala, 11 Ben Lam, 10 Simon Hickey, 9 Kaito Shigeno, 8 Akira Ioane, 7 Mitch Karpik, 6 Taleni Seu, 5 Scott Scrafton, 4 Michael Fatialofa, 3 Ofa Tu'ungafasi, 2 Greg Pleasants-Tate, 1 Sam Prattley.
Replacements: 16 Kurt Eklund, 17 Marcel Renata, 18 Isileli Tu'ungafasi, 19 William Lloyd, 20 Matt Matich, 21 Jono Hickey, 22 Mitch Hunt, 23 Reiko Ioane.
Referee: Paul Williams