But after the Champagne was poured, the couple vowed to spend the winnings on houses, cars and travel.
Fresh Choice Green Island owner John Moyle said he was attending a function at Green Island Rugby Football Club on Saturday night when he received a text asking if he could open his supermarket to check a possible big-winning Lotto ticket which had been purchased at Pak'n Save Dunedin.
The ticket-holders were "a friend, of a friend, of a friend'' of his wife, Julie.
Mr Moyle called his checkout supervisor to ask her to meet him, Mrs Moyle and the ticket-holders at the supermarket.
The supervisor was "shaking'' as she put the ticket barcode to the scanner.
The machine beeped and the screen read: "Claim: $13.36 million''.
"We had a beer and a Champagne in store and started doing the paperwork and Lotto rang,'' Mr Moyle said.
Being part of such a big win was "unbelievable'', he said.
"I was stoked, so I don't know how they coped ... I struggle to grasp having that amount of money go into your bank account and they were the same - they were over the moon, but were in disbelief.''
The couple talked about spending the money on houses, cars and travel.
Mr Moyle did not know the couple and did not ask them their names: "I didn't want to know. We know their friends but we didn't know who they were ... that means I can't tell anybody, which suits me fine.''
After returning to the club, he told those at the function a Dunedin couple won with the ticket.
Everyone was pleased.
"Everyone is happy Dunedin got a big prize - sure we all wanted it to be us - but the fact it was Dunedin was great.''
The three winning tickets were sold at Pak'n Save Dunedin, Oparau Roadhouse, near Te Awamutu, and online at MyLotto, to a player from Hamilton.
Lotto spokeswoman Emilia Mazur said last night they were yet to hear from the two other big winners.
Pak'n Save Dunedin Lotto supervisor Abby Pegg said she was checking the tickets of hopeful players yesterday and most were disappointed with the result.
"I'm just breaking people's hearts,'' she said as she scanned another "not a winning ticket''.
However, four people were given $600 for division three wins.
The supermarket had sold 25 division one tickets before, but the latest win was the biggest, she said.
Lotto NZ spokeswoman Emilia Mazur said the $13.36 million win was the biggest in Otago since Lotto began in 1987.
The second biggest win was $9.7 million in April 2010.
Lotto NZ Chief Executive said there were more than 2.7million tickets entered in Saturday's draw.
More than 3000 tickets were sold every minute between 5pm and 6pm on Saturday.
Nearly $60 million was spent at Lotto outlets across New Zealand last week and sales for Saturday's must-be-won draw accounted for about $40 million of that.
Results
Tickets bought at Pak'n Save Dunedin, the Oparau Roadhouse in Te Awamutu and online in Hamilton shared the rolled down prize in Powerball on Saturday, each winning more than $13 million.
Lotto: 3, 18, 27, 29, 33, 37. Bonus: 36. Division 1, $142,857 (7, Gisborne, Tokoroa, Takanini, Papakura, Mairangi Bay, Te Atatu South and Henderson); division 2, $19,499 (51); division 3, $610 (1696); division 4, $62 (3987); division 5, $32 (66,295); division 6, $24 (84,106).
Strike: 29, 27, 37, 18. Strike 4, $405,792 (2, Auckland and Waipapa); Strike 3, $831 (222); Strike 2, $82 (12,517); Strike 1, bonus ticket (320,472).
Powerball: 7. Division 1, rolldown (0); division 2, $13,344,189 (3); division 3, $178 (175); division 4, $20 (389); division 5, $10 (6821); division 6, $10 (8411); division 7, $12 (90,359)
