Three players scored doubles: prop Jonty Bird, hooker Jack Yarrall and halfback Lindsay Horrocks.
Second-five Opetini Dryden scored their opening try while first-five Tim Goodwin slotted a penalty and three conversions.
Down 24-5 at halftime, Kaierau made a solid comeback as winger CJ Stowers scored his second hat-trick this season, while second-five Nemia Adrole also dotted down and fullback Rusiate Lalanabaravi added one conversion.
Meanwhile, the Division 2 competition was turned on its head as both the unbeaten points table leaders suffered away-game losses to their fellow Top 5 opponents.
Down 22-0 at one stage, Direct Connect Marist Celtic staged a remarkable comeback in the final quarter to upset Utiku Old Boys 43-32 at Spriggens Park.
Kelso Hunterville regained the Challenge Shield they had previously lost to Celtic by holding off competition leaders RockGas Whanganui Pirates 19-17 at their domain.
Like Hunterville, Marton also pushed themselves almost out of reach of sixth-placed Border with a 44-10 win over Gemini Pepper Construction Kaierau at the Country Club.
With their Division 1 team on the bye, Horizon Networks Taihape were able to marshal full player resources for their Memorial Park clash with Whanganui Can-Am Counties, winning 43-12.
The Tasman Tanning Te Awa Wahine competition saw AGC Marist Clovers do the business in their WRFU derby with Silks Audit Rātana, winning 42-15 on Friday night at Cooks Gardens.
Push on this weekend to avoid relegation
It is now sudden death time for the Ruapehu side in the race to avoid Division 1 relegation as they host Wanganui Car Centre Kaierau at Rochfort Park this Saturday.
However, after consecutive Premier grand final appearances, fifth-placed Kaierau have hit a slump this campaign with four straight losses, although they have picked up bonus points throughout. With the bye in the last weekend before the split into three competitions, they need to finish the first half of the season strong.
After narrow away defeats in their past two games, sixth-placed Silks Audit Rātana also need to push clear of Ruapehu, but will have a tough ask against a confident Dave Hoskin Carriers Marist at the Pā.
It will be a cracking afternoon at Memorial Park with three games, headlined by the big east versus west rivalry, as Byfords Readimix Taihape try to regain the Challenge Shield they lost on the same ground to Waverley Harvesting Border at the end of the 2025 Premier round-robin.
Draw, May 15–16
Division 1
2.45pm kickoffs
Ruapehu v Kaierau, Rochfort Park; Challenge Shield - Taihape v Border, Memorial Park; Rātana v Marist, Rātana Pā; Bye: Counties.
Division 2
1pm kickoffs unless noted (times subject to change)
May 15: Counties v Marist Celtic, Macnab Domain, 6.30pm.
May 16: Challenge Shield – Hunterville v Kaierau, Hunterville Domain; Utiku Old Boys v Marton, Memorial Park; Taihape v Border, Memorial Park; Bye: Pirates.
Tasman Tanning Te Awa Wahine
May 15: Bush v Rangitīkei, Bush Park, 7.30pm; Kia Toa v Taihape, Central Energy Trust Arena, 7.30pm.
May 16: Rātana v OBM, Rātana Pā, 1pm; Freyberg v Marist Clovers, Colquhoun Park, 1pm.