Three heats were run on Friday night and two more on Saturday night before 24 cars contested a 20-lap final.
Robertson recorded a first, a second, two fifths and a seventh in the five heats.
“I went into Saturday night the second-highest on points and did enough in the two remaining heats to take seventh position on the starting grid in the final,” he said.
“I made a bit of a mess of the start and dropped back to 12th. Luckily, a yellow light came on four laps in and we got bunched up again.
“Then I had to make a lot of passes to get up into third.”
Robertson raced side by side with a car from Invercargill for three or four laps in the closing stages of the final before getting round him for third place.
“There was no more than a car-length between each of the top four cars in the end,” he said.
“It was definitely close and intense racing all weekend.”
Robertson said he was over the moon to cross the finish line in third place.
“I kept saying to myself, ‘Really!? Did I actually do this?' ”
His stepfather Doug Walsh went to the titles with him.
“Doug was over the moon. In fact, I think there was a tear or two.”
The pair arrive back in Gisborne tomorrow night. The car already has the 3NZ stickers displayed.
“We put those on in Queenstown yesterday,” Robertson said.
“We designed them ourselves and they look pretty awesome.”
He wanted to thank Law Haulage Ltd, who supported him.
“Without ‘AJ' Law, we wouldn't have made it down here.”
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