On a beautiful day under the mountain for running rugby, Ruapehu's backline did themselves no favours in the first stanza with bobbled passes and shallow line kicks.
Despite missing key forwards like captain Peter Rowe (illness) and lock Sonny Woodmass (sternum injury), Ruapehu found their traction with 10 quick points midway through the second spell, including a try to flanker Dylan Pearce after a rumble off lock Nick Cranston's lineout take.
But after playing at a quick and physical pace right from the opening minutes in the relatively warm conditions, both teams were nearly spent.
Aggressive hooker Cole Baldwin and lock Sam Madams, who always lifts when facing respected opponent Cranston, were outstanding, while Ruapehu flanker Andrew Evans and recently returned reserve forward Fraser Hammond gave it everything to force one last score.
In the backline, Border halfback Lindsay Phillips was his team's linchpin in a good tussle with opposite William Short, while Ulukuta was the fastest player on show and looked dangerous with nearly every touch of the ball.
Having brought only 18 players north, Border coach Ross Williams was relieved with his team's first win over Ruapehu since they rejoined Wanganui rugby in 2011.
"It gives us belief in what we're doing and trying to achieve.
"The tries in the first half were some of the best we've scored.
"To be able to counter that Ruapehu maul is massive. I'm really proud of the effort in the last five [minutes] because we were blowing hard."
Ruapehu coach Chris Winter said they had been taught a valuable lesson that more work is still needed in the next five weeks.
"Missed throws and knock-ons at lineout time, decision making here and there. Our mental game wasn't on [but] the boys were quite rapt with the last bit of the second half."
Knowing it would be a long day, Border's coaching staff did not even get excited as their pack worked off Laurie's runs to drive straight to Ruapehu's line, with Horrocks shifting wide for Ulukuta to go over in the corner.
That pessimism was well founded as Ruapehu immediately hit back, getting a free kick for the lineout, and after committing Border defenders close to the driving maul, Short spun it wide for an unmarked Owen King to score on the wing for 5-5 after eight minutes.
Border looked for points wherever available with Ulukuta taking several kicks and landing a couple of penalties.
Ruapehu still struggled to maintain meaningful possession and then Border blew the game open as Skedgwell, Hamilton, and centre Sailosi Naqiso all handled to send Ulukuta flashing down the far touchline.
Madams and Baldwin followed it up with surging bursts, before Horrocks pulled a switch play with flanker Liam Richardson and Hamilton did the rest, stepping through the last tackler to score.
Ruapehu finally began to put continuous phases together after halftime, and after getting a scrum penalty, Cranston was driven from the lineout and again his team caught Border napping with Pearce going over on an unmarked blindside.
Second-five Tautahi Rawiri added a penalty shortly afterwards to set up a pulsating final quarter, where it seemed Ruapehu had all of the ball but Border met them at every turn to hold on till the final whistle.
Waverley Harvesting Border 18 (Andy Hamilton, Sikeli Ulukuta tries, Ulukuta 2 pen, con) bt McCarthy's Ruapehu 13 (Owen King, Dylan Pearce tries, Tautahi Rawiri pen). HT: 18-5.
