From there a Wells' second-half penalty was the only addition to the scoreline.
Taihape's win and Integrity Motors Pirates' upset loss to Harvey Round Motors Ratana in the Pa leaves the race wide open for the second spot on the table and a home semifinal.
After the disappointment of losing the shield the previous week, McCarthy's Ruapehu have now found themselves with breathing space at the top of the table after getting a bonus point in their 30-8 disposal of Speirs Food Marton in the only away victory of the weekend.
Logan Vaughan, Roman Tutauha, Owen King, Tautahi Rawiri all crossed for the defending champions, with Marton getting a sole reply through Eric Sagapolutele in the second half.
It was a real slog at the Country Club as a sole try by Perofeta Fuaava proved enough to carry Wanganui Car Centre Kaierau to a 5-3 win over Utiku Old Boys in the lowest-scoring game of the season. Taylor Transom kicked a penalty for the visitors in the first half, with neither side able to expand on their total in the next 40 minutes.
In senior rugby, the separated championship and consolation grades kicked off on Saturday with Tech making their first official defence of the Stihl Shop Wanganui Challenge Shield, beating Border 22-13 at Spriggens Park. Marist Celtic won the Spriggens Park derby over Trans Pacific Pirates 17-3 to stay in touch with defending champions Power Farming (PN) Hunterville, who squeezed past Ruapehu 10-5.
In the consolation grade, Marton stay on top with the bye week, alongside Counties who beat Taihape 10-8, while at the bottom of the table, Kaierau's 10-5 loss to Utiku Old Boys saw them earn their first competition point, but they have now gone 13 straight games without a win.
Results, June 21
Tasman Tanning Premier, Week 14
Wanganui Car Centre Kaierau 5 (Perofeta Fuaava try) bt Utiku OB 3 (Taylor Transom pen). HT: 5-3.
Harvey Round Motors Ratana 24 (Kane Tamou, Jamie Hughes tries, Te Tua Kemp pen, Western Hemi 3 pen, con) bt Integrity Motors Pirates 16 (Timoci Ului, Brett Turner tries, Manulua Lafi 2 pen). HT: 11-3 Pirates.
McCarthy's Ruapehu 30 (Logan Vaughan, Roman Tutauha, Owen King, Tautahi Rawiri tries, Rawiri 2 pen, 2 con) bt Speirs Food Marton 8 (Eric Sagapolutele try, Jake Karaynidis pen). HT: 20-3.
Grand Hotel Challenge Shield - Taihape 29 (Rimu Wipaki, Tremaine Gilbert tries, Tom Wells 5 pen, 2 con) bt Waverley Harvesting Border 7 (John Laurie try, Sikeli Ulukuta con). HT: 26-7.
Bye: Dave Hoskin Carriers Marist.
Grand Irish Bar Most Valuable Player points
At Kaierau: Josh Edwards (Kaierau halfback) 3 points, Richard Minty (Utiku OB lock) 2, Samu Kubunavanua (Utiku OB centre) 1.
At Ratana: Charlie Mete (Ratana flanker) 3, Manulua Lafi (Pirates No 8) 2, Faalafi Vave (Pirates flanker) 1.
At Marton: Andrew Evans (Ruapehu flanker) 3, William Short (Ruapehu halfback) 2, Steve Wulf (Marton flanker) 1.
At Taihape: Marcus Tottman (Taihape flanker) 3, Tom Wells (Taihape first five) 2, Lindsay Horrocks (Border halfback) 1.
MVP Leaders: Lindsay Horrocks (Border) 16 points, William Short (Ruapehu) 14, Ryan Gill (Marist) and Manulua Lafi (Pirates) 11, Sikeli Ulukuta (Border), Vaan Rauhina (Ratana) and Clive Stowers (Pirates) 10, Darren Munro (Kaierau) 9, Marcus Tottman (Taihape), Jamie Hughes (Ratana) and Ray Stark (Border) 8, Sikeli Ulukuta (Border), Hoani Rameka (Utiku OB), Nick Cranston and Andrew Evans (Ruapehu) and Simon Hillis (Pirates) 7, Isaac Greer (Marton), Zyon Hekeni (Ruapehu) and Rory Gudsell and Simon Dibben (Marist) 6, Ephraim Reynolds and Josh Edwards (Kaierau), Logan Vaughan (Ruapehu), Junior Tume (Pirates) and Jaye Flaws and Dane Whale (Taihape) 5, Brett Nicholls, Ritchie Iorns and Tom Wells (Taihape), Matt Crawford (Utiku OB), Roman Tutauha (Ruapehu), Scott Komene (Ratana), Chris Rayner (Marton) and Michael Nabuliwaqa (Utiku OB) 4, 14 players with 3 points each.
Senior Championship, Week 14
At Spriggens Park (Stihl Shop Wanganui Challenge Shield): Tech bt Border 22-13. HT: 17-3.
At Spriggens Park: Marist Celtic bt Trans Pacific Pirates 17-3. HT: 10-3.
At Hunterville: Power Farming (PN) Hunterville bt Ruapehu 10-5. HT: 10-5.
Senior Consolation, Week 14
At Kaierau C.C: Utiku OB bt Kaierau 10-5. HT: 10-0.
At Ratana Pa: Marist Buffalo's bt Ratana 29-5. HT: 12-5.
At Memorial Park: Counties bt Taihape 10-8. HT: 8-7 Taihape.
Bye: Marton (4 points).