"Number 5 is my lucky number so I always choose to play it. When I saw that it was the winning number, I thought 'well that's a good start'," he said.
He then quickly noticed he had matched the first three numbers on the same line.
"It wasn't until I saw that I had the next three numbers as well that it really dawned on me what it all meant — I was $10.2 million richer!"
He then phoned his sister, who was in disbelief at the news.
"When I told her how much I'd won, she didn't believe me. She wanted to see the ticket herself so came racing over to my place and together we checked it on the Lotto NZ App.
"Sure enough when we scanned it, the words 'Major Prize winner' appeared. It was all the confirmation I needed."
Despite knowing that he was holding onto a multi-million dollar ticket, the winner decided to pop his ticket in his safe and sit on it for the next week.
"I had a few work commitments and I wanted to get everything in order before I went to Auckland to claim the prize," he said.
One of those things on his to-do list was sharing the news with his kids.
"I invited everyone over for a pizza night and told them that I had some exciting news to share," he said.
Initially he told his kids he had won $250,000 on Lotto - and watched as they erupted in celebration.
"That's when I told them, 'well you better add $10 million to that!' It took a few moments for them to click what I meant, but then the excitement really kicked off!"
Claiming his prize in person at Lotto New Zealand's head office this week, the winner has had some time to think about how he might spend the spoils.
"I want to start ticking things off my bucket list, so the first thing I want to do is go travelling. Escaping to a European summer sounds like a good idea to me."
The winning ticket was sold at Whitcoulls the Base in Hamilton for the draw on June 15.
This is the tenth time Powerball First Division has been struck so far this year.