Canterbury, chasing a fourth straight domestic crown, lead the field with 29 points as they head south to play Otago. A five-point win will ensure they host the final next Saturday.
Win without a bonus point and Waikato come hard into the hosting equation. They entertain Auckland today.
A Canterbury four-point win in Dunedin, combined with Waikato getting a bonus point win over Auckland would have the Mooloos top qualifier. They beat Canterbury in their round robin game, which is the first tiebreaker in the event of teams having the same number of points.
Auckland, sitting fifth, aren't out of the picture, but must get five points against Waikato and hope three of Canterbury, Waikato, Taranaki - who defend the shield against Hawkes Bay tomorrow - and Bay of Plenty, who visit dispirited Southland, slip up.
Taranaki's jubilation at winning the shield in Invercargill will be doubled should they hold off Hawkes Bay, and either Canterbury or Waikato stumble.
So it's all to play for, and Auckland, well rested with a week off, should be up for a decent crack in Hamilton.
Last season produced a couple of tight contests. Waikato won the round robin clash 21-18, then pipped Auckland in the semifinal, 38-37 with some late heroics.
Auckland have made just two injury-forced changes, with locks Chris Lowrey and Liaki Moli out.
Lowrey has had a strong campaign but picked up an elbow fracture and is sidelined for a month. Moli redamaged the shoulder which kept him out for months earlier this year and is due for a scan next week.
Josh Katene and the distinctly promising Steven Luatua take their places.
"They'll be looking at where they sit on the table and they'll realise that a win against us guarantees them a final," Auckland coach Mark Anscombe said. "So both teams ... will want to get the result."
Waikato have unwanted All Black loose forward Liam Messam and Bath-bound first five-eighth Stephen Donald back for the game.
Waikato v Auckland
Hamilton, 2.35 today
Trent Renata
Henry Speight
Save Tokula
Jackson Willison
Tim Mikkelson
Stephen Donald
T Kerr-Barlow
Alex Bradley
Marty Holah
Liam Messam
Romana Graham
Toby Lynn
Nathan White
M Cummings-Toone
Toby Smith
Reserves: Vance Elliott, Ben May, Matt Vant Leven, Zak Hohneck, Brendon Leonard, Sam Christie, Declan O'Donnell, Ted Tauroa.
Dave Thomas
Joe Rokocoko
Hadleigh Parkes
Winston Stanley
George Moala
Gareth Anscombe
Alby Mathewson
Peter Saili
Sean Polwart
Nathan Hughes
Steven Luatua
Josh Katene
Charlie Faumuina
Tom McCartney
Pauliasi Manu
Reserves: Nathan Vella, Angus Ta'avao, Richard Haddon, Ben Masoe, Toby Morland, Piers Francis, Brent Ward, Tevita Mailau.