"I sat there checking the ticket over and over again, ticking the numbers off one by one," her husband said.
"When I was sure I had the winning ticket, I said to my wife: We've nailed it."
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The winners, who chose not to be named, spent a few days letting reality sink in - and didn't let the winning ticket out of their sight.
"We kept a close eye on that little piece of paper," the husband said. "When we were at home it was in the safe, and whenever we went out I tucked it in the pocket inside my coat."
The winners flew up to Lotto's Auckland office to claim their prize as soon as they could, Lotto spokeswoman Kirsten Robinson said. They wished to remain anonymous.
It was the first Powerball First Division winning ticket ever sold in Feilding
Meanwhile, two Oamaru lotto winners who scooped $800,000 have yet to come forward to claim their booty.
The North Otago town struck gold in the last fortnight, with one ticket sold at the town's PaperPlus store netting $600,000. Another, bought at Lotto 'n Things, was the $200,000 First Division winner.
Lotto said it was rare for the town to have such big back-to-back wins in successive weeks.
Lotto 'n Things owner Jan Denny, who owns the shop with her husband Paul, told the Oamaru Mail it was fantastic having a winning ticket bought from her store. "We are all eagerly awaiting the winner's arrival to congratulate them," she said.
Oamaru Paper Plus owner Dick Cottier said the $600,000 ticket bought from his store still hadn't been claimed.
"I'd imagine that the ticket was bought for someone as a Father's Day present and they haven't checked it yet or it's gone to someone outside of the town," Cottier said.