It was a game effort from the visitors, led by young first-five Tyler Rogers-Holden and some powerful runs from Chase, lock Meni Taufaasau and flanker Steve Wulf.
However, in their attempt to negate the towering Woodmass in the lineout, Marton spent the first half throwing to the back jumpers, where they constantly spilled the ball or dropped it.
They also lacked for a true organiser and tactical kicker as while Rogers-Holden is a competent first-five, his true strength is at halfback, where he switched back when player-coach Cornel Mason subbed himself off and goalkicking winger Jacob Karaynidis moved in to run the cutter.
There was a familiar face filling in at prop as well with Bulls' builder Andy Walker, known from The Block NZ television show, joining the team for their trip north.
Still awaiting key representative players like Nick Cranston, Roman Tutauha, Pehira Huwyler and Logan Vaughan, Ruapehu coach Chris Winter said despite his team's transient look, they still needed to work on finding collective form.
"It's more man management.
"The guys that are playing are doing as adequate a job [as possible]. It's just the combinations are not quite there.
"You just have to trust that the boys can pull through.
"[Marton] feel as though they won. Course, we feel we won too."
Mason also acknowledged his 'nice-to-have' list would include someone to back up Rogers-Holden.
"That's all we need a really good playmaker.
"We probably lacked a bit of execution in the lineouts. The last three weeks that's been sluggish.
"But I give the heads up to the forwards for giving us some sort of ball. With the dry weather, we might have been able to pull it off."
Marton had early territorial advantage with busy fullback Dane Cowley going close to scoring as Chase and second-five Peter Hay-Horton ran hard.
But constant fumbles in the lineout cost them momentum as Ruapehu winger Keiran McPherson all but scored in the top left corner with Cowley and Karaynidis bundling him out.
Ruapehu's pack got them key yards and forced the infringement for fullback Zyon Hekenui to open the account. Then Rogers-Holden made immediate amends for a bad pass in a Marton set-move breakdown by scoring an excellent individual try from a scything run where he beat three tacklers.
Working off Marton's lineout woes, Ruapehu's pack drove right to the line but lost the ball on the halftime whistle.
Given a rark up, they responded straight after the break by camping in Marton's 22m zone, with first-five George Williams putting Woodmass over beside the posts.
Turning down a gift penalty, Ruapehu opted to keep the pressure on and were rewarded in the 62nd minute as Rowe finished off a dash by halfback William Short to score from the ruck.
Ruapehu swarmed or charged down Marton's clearances, which led to another Hekenui penalty from good position to seemingly wrap the game up.
But after Greer caught them asleep at the kickoff, Marton closed the gap for a tense finish in the rain.
McCarthy's Ruapehu 20 (Sonny Woodmass, Peter Rowe tries, Zyon Hekenui 2 pen, 2 con) bt Speirs Food Marton 14 (Tyler Rogers-Holden, Isaac Greer tries, Jake Karaynidis 2 con). HT: 7-3 Marton.