But crucial changes at halftime saw Lindsay Horrocks and Lasa Ulukuta enter the fray at halfback and No8 and from the 41st minute onwards Wanganui were a different outfit.
Ulukuta taking passing off the back of the scrum for Horrocks at first receiver injected extra yards of pace, and with the big loosie charging straight up the middle while the young Horrocks barked constant instructions to the rest of the forwards, Wanganui flipped the momentum.
It was like a brain transplant between the teams Wanganui's cause helped immersibly by South Canterbury pushing passes, Kotobolavu's sinbinning, crucial turnovers, and missing touch from basic free kicks.
If any two players typified the switch it was Wanganui origin flanker Doug Horrocks and import centre Jason Temara.
Decidedly average in the first half but now working off a platform, Temara was devastating out wide while Doug Horrocks wrenched control of the breakdown as South Canterbury fell behind with 14 minutes left and never got back within cooee of Wanganui's 22m.
In his 50th game, fullback Ace Malo started the comeback with a dynamic run leading to flanker Andrew Evans scoring Wanganui's first try, while first-five Areta Lama redeemed his first half sinbinning for infringement by shelving his running game in favour of smart chip kicks to the corners.
That Wanganui's forwards gained ascendancy is all the more impressive considering they played without inspirational captain Peter Rowe and lost lock Nick Cranston by halftime Sonny Woodmass filling the breech admirably.
Tellingly, stand-in captain and tryscoring prop Vaan Rauhina said despite the score, halftime discussion revolved around staying calm and actually putting training into practice.
"In that first half a lot of mistakes, pressure passes, it wasn't sticking."
Lindsay Horrocks and Ulukuta were the first to successfully apply themselves and Rauhina said from the Evans try the team got their confidence back.
"That's the leisure of having our squad 22 key players."
He said the best thing now was while the problems with execution have not dissipated, Wanganui at least have the win and momentum they needed.
"By no means are we satisfied with what we produced out there."
Relieved coach Karl Hoskin said by halftime there was nothing more his coaching staff could have added it was up to the senior guys and they finally delivered.
"We got to the point where we were 'over-saying' things you've just got to stand up and have a go.
"[Ulukuta, Lindsay Horrocks] provided that go forward. Also, Doug Horrocks did the things you didn't see."
While both teams wound up dominating with the wind at their backs, Hoskin said it was not that much of an advantage.
"It's all upstairs [thinking], the wind is just how it works."
South Canterbury first-five Sam Vaevae and Wanganui's rookie winger Zyon Hekenui traded penalty kicks in the opening ten minutes.
Both squads had horror restart recoveries Hekenui's penalty came after a South Canterbury fumble and then his team repaid it as the visitors swooped straight to Wanganui's line, with Tafa barging over.
Vaevae added another penalty following a bizarre 'miss' when the ball fell over during his run up and he knocked on picking it up.
It was all South Canterbury as they pounced on another poor Wanganui lineout, with fullback Kurt Rooney combining with winger Aporosa Tabulawaki and hooker Nathan Tubb to put Rooney over after 30 minutes, before another Vaevae penalty made it 23-3.
Hekenui replied right on halftime but Wanganui looked overmatched heading into the sheds.
Instead, they exploded into the second half as Malo cut straight through and brought his team right to the tryline.
A quick tap after the first of many South Canterbury infringements and the ball was spread to Evans to dive over in the corner.
Ulukuta made another bust to go back on attack Hekenui landing the penalty for 23-14 while South Canterbury went to pieces, being in front at the restart.
Lama trapped South Canterbury in their corner and from a clean Woodmass lineout take, the forwards put on a perfect rolling maul for Rauhina to burrow over.
Ulukuta, Temara and Tauailoto were running hot and with Kotobolavu binned for lazy running in front of the posts, Hekenui took Wanganui to the lead.
South Canterbury grasped back possession but Wanganui's tackling kept them outside striking distance as the clock wound down.