Coaches Craig Scanlon and Craig Neill, learning with bitter experience from 2014 when Buller lost the Meads Cup final to Mid Canterbury after an unbeaten run, have tried to manage their players more carefully this year to leave something in the tank, which means Wanganui should likely face a better side than the Buller they held scoreless in the 28-0 win in Westport on October 8.
But Wanganui coach Jason Caskey has played his cards just as carefully after a long season, which began in late July with the build-up to the Ranfurly Shield challenge.
And the wise heads of his team might not have the game experience of Brownlee and Beveridge, but they sure have played in more fixtures when the silverware was on the line.
"You've got Peter and Cole [Baldwin], you've got a few that have been rocking around for an age. They're invaluable to a team. That's what Heartland's all about."
While winger Te Rangatira Waitokia, who with 12 tries could still break the Heartland record of 14, may "set the world on fire", it is the veterans doing the hard yards in the middle that will lay on those opportunities.
Another to do that work is skilful prop Viki Tofa, a player Caskey approached last year to stick with representative rugby after withdrawing from the club season.
Tofa's journey will culminate in a New Zealand Heartland XV jersey in coming weeks.
"Well deserved, he's been outstanding for us this year. Probably the best front-on defender in the team. A great worker," Caskey said.
Looking to counteract Stephens and Lash will be Wanganui's Dane Whale and Lindsay Horrocks, who had their best games in the semifinal shutout of Wairarapa Bush.
Usually, Whale and Horrocks decide among themselves who takes charge as the main tactical kicker, but both of them were so pinpoint in the playoff that they alternated the role.
"They've both got to be able to do it, it's just whether it's better coming from No9 or No10 [on the day]," Caskey said.
The semifinal performance meant Caskey was resolved to keep faith with the same 22 for this game, unfortunately squeezing out players who would be sure-fire starters in any other team or season.
Only dynamic midfielder Kameli Kuruyabaki could possibly force his way back in through the bench, although Caskey was doubtful his rolled ankle would pass last night's fitness test.
Prop Tietie Tuimauga got the thumbs up as limping off last weekend was diagnosed as severe cramp rather than a pulled muscle, so Wanganui's other loyal forwards will have to be spectators on the day.
"It's hard on Tremaine [Gilbert] and Renato [Tikoisolomone]," said Caskey.
"That's just how it goes with Campbell [Hart] at No6, being strong at lineout time and carrying strongly."
For Caskey, game momentum will be everything tomorrow, given Buller and Wanganui have the ability to open up a dozen scoring opportunities in a regular match but, in the pressure of a grand final, those chances could drop as low as four.
"If you blow three of them, you're going to struggle.
"You always have the endeavour - you have a go but usually both sides are well up to it. It will come down to the accuracy."
Buller, specifically Lash, like to run if they get open air in front of them, with speedy backs Setefano Sauqaqa and Peni Nabainivalu being the tryscorers in their upset semifinal win over South Canterbury in Timaru.
"You don't have four Fijian boys in your team if you're going to play kicking rugby," said Caskey.
"We have to nullify those threats.
"It would be great to see a good crowd there. It'd be nice to get 3000-5000, I don't see why we couldn't.
"You've got two teams that love to play rugby and throw the ball around."
Whatever happens, Caskey wanted to thank his entire team for their work this season, starting from WRFU chief executive Bridget Belsham for holding the ship together.
Assistant coaches Jason Hamlin and Shane Ratima brought all their expertise, while the management of Chris Back and Marty McGrath took care of everything.
The medical crew of Kent Stembridge, Graham Hill and Deb Koubaridis worked overtime to address the rising injury toll, while videographer Kate Soutar provided priceless match footage.
Kickoff for the final is 4.30pm.
Teams
Wanganui
1. Tietie Tuimauga; 2. Roman Tutauha; 3. Viki Tofa; 4. Sam Madams; 5. Gavin Thornbury; 6. Campbell Hart; 7. Peter Rowe (Capt); 8. Malakai Volau; 9. Lindsay Horrocks; 10. Dane Whale; 11. Michael Nabuliwaqe; 12. Craig Clare; 13. Blake Hohaia; 14. Te Rangatira Waitokia; 15. Asalemo Malo.
Reserves - Forwards: 16. Cole Baldwin; 17. Hamish Mellow; 18. Bryn Hudson; 19. Jamie Hughes. Backs: 20. Kane Tamou; 21. Simon Dibben/Kameli Kuruyabaki; 22. Samu Kubunavanua.
Buller
1. Logan Mundy; 2. Anthony Ellis; 3. Phil Beveridge (co-Capt); 4. Ciaran Neilsen; 5. David Egelstaff; 6. Blair McIlroy; 7. Luke Brownlee; 8. Daniel Hytongue; 9. Andrew Stephens (co-Capt); 10. James Lash; 11. Setefano Sauqaqa; 12. Penijamini Nabainivalu; 13. Joshua Tuidriva; 14. Petaia Saukuru; 15. Anthony Tailua.
Reserves - Forwards: 16. Jareth McKay; 17. Glen Duncan; 18. Lochie Elley; 19. Simon Abel. Backs: 20. Luke Watson; 21. Stephen Crackett; 22. Matthew Bonisch.