Columb had dominated the first two rounds of the championship but struck some bad luck in the third round on the Harrisville circuit.
The injured Yamaha rider laboured to two fourths and a sixth in his three MX2 (250cc) races.
Fortunately for Columb, his main rival, Australian visitor Brock Winston (KTM), also had a difficult round.
Winston finished 6-4-3 in his three outings, enough to end the day marginally ahead of Columb, but the Australian reduced the championship deficit by only two points and it will take a huge dose of luck in Taupo in a fortnight if he is to snatch away the Kiwi crown.
The day's winner in the MX2 class was another Australian, Suzuki's Ryan Marmont. He managed 8-2-1 results on Sunday but it was his debut appearance in the series and he will not be able to accrue enough points to claim the title.
Mount Maunganui's Cody Cooper continued his dominance of the MX1 class, winning all three races to push his lead in the class to 31 points.
In the 125cc class, Rotorua's Cameron Vaughan (Yamaha) had an up and down day, finishing third in both the early races as his main rival, Te Puke's Logan Blackburn (Yamaha), raced to victory and took over the championship lead.
But Vaughan struck back in race three, winning it in style as Blackburn struggled to fight through traffic and settled for fifth, handing the championship lead straight back to Vaughan.
Just four points separate the pair ahead of the final round in Taupo.
