At Rochfort Park, Ruapehū and Marist are now separated by four points on the table with two regular season games left after Saturday.
With none of the bottom three teams having secured a win over the semifinal-locked sides this campaign, both are painfully aware whoever gets their nose in front after this weekend is very likely to stay there.
"In short, it's a quarter-final for us. It's a must-win," Marist coach Travers Hopkins said.
Having given their blood to beat Ngamatapouri 28-5 on August 8, an undermanned Marist hung with Taihape as long as they could at Memorial Park, deadlocked 10-10 at halftime, but were disappointed they could not leave with even a bonus point to put space on Ruapehū - losing 36-10.
"Come the second half, they were able to throw a few sets of fresh legs on ... we had three on the bench," Hopkins said.
"Taihape played well, they're a class side. They're not defending champs for no reason."
Marist paid a big price, as after playing every minute of every game so far, their try-scoring and drop-kicking prop Viki Tofa had to come off injured, while plenty of other bodies were pretty sore that evening.
Hopkins admits it is a race against time for Tofa to front on Saturday, and they will desperately need him as the experienced player who will not be intimidated by the remaining Steelform Wanganui representatives in Ruapehū's pack.
"He would be at best 50-50 for this weekend.
"If he can't lace up, it's a huge loss – you're going against the Hakaraia boys and the Heartland loosies.
"We're putting a few calls to a few different people to have a full complement."
If Tofa can't play, just add yet another handful of assignments to Marist's nuggety hooker Jack Yarrall, who Hopkins said is having an outstanding campaign.
"He's doing what you would call his core role, but then he's also doing stuff that backs would be envious of."
Marist were put through an intense training session by guest coach Darryl Malcolm at Cooks Gardens on Tuesday, and while a narrow loss with bonus points on Saturday might just be enough to hold off Ruapehū and Ngamatapouri to limp into the semifinals, Hopkins would much rather this is won and done.
"You want to keep fate in your own hands if possible."
Ruapehū manager Mark Green agreed his side did not want to waste mental energy on the machinations of bonus point scenarios either.
"We're trying not to focus too much on the equations and staying on the match itself.
"If you don't, and you're worried about four tries, you're not 100 per cent into your game plan."
Many fringe players who were not regular starters during Ruapehū's most recent heyday – the 2017-18 Premier titles and an 11-1 regular season before Taihape's semifinal upset last year – have needed extra time to get familiar with each other, but the signs were promising against Ngamatapouri.
"The boys have picked their tail up after that win on Saturday," Green said.
"The attack is pretty good, just got to get the discipline and the defence really.
"All in all, everyone's in pretty good shape."
For example, either through injury or unavailability, Kahl Elers-Green, Troy Brown and Royce Trow did not start playing together as the regular No 10-13 lineup until a couple of games ago – Brown and Trow combined for five tries last weekend.
"The boys are starting to find their feet; the combinations slowly coming together," Green said.
"It's taken more than a little while, I suppose."
In the third game, Wanganui Car Centre Kaierau will be looking for maximum points when they host Ngamatapouri at the Country Club, given Taihape have drawn level with them and could yet swipe the second precious home semifinal spot.
Mathematically still in contention for the top four themselves, Ngamatapouri will be after any points they can get.
Not reported at the weekend, but their try-scorers were Epeli Delasau with a hat trick, Te Rau Wirihana a double, then Timoci "Jim" Seruwalu , while Hone Taurua had a good kicking game with 13 points.
The draw is:
Premier (2.30pm kickoffs): Border vs Taihape, Dallison Park; Kaierau vs Ngamatapouri, Country Club; Ruapehū vs Marist, Rochfort Park.
