Michael Bracewell hit a record-breaking 24 in the final over to clinch a one-wicket win for New Zealand against Ireland in the ODI opener at Malahide.
The Black Caps needed 20 from the last over for victory to beat the previous best of 18 set by England against Australia in 1987.
Bracewell smashed three fours and two sixes to win it with a ball to spare.
Harry Tector made 113 in Ireland’s 300-9 and the tourists struggled before the late fireworks from Bracewell.
It was another heartbreaking defeat for Ireland at the Co Dublin venue after losing to India by four runs in their second T20 game last month.
“It is a pretty sombre dressing room at the moment,” said Ireland captain Andrew Balbirnie.
“We did everything right from most of it, but the last 10 overs Michael played really well.
“We have put in a good performance, but we are in the results business and being 1-0 down hurts.”
New Zealand captain Tom Latham won the toss and his decision to field first in the World Cup Super League game looked a good one after the early dismissals of openers Paul Stirling and Balbirnie.
Tector again showed his immense promise with a superb innings as he laid the foundation for a healthy Irish total.
A 64-run partnerships with Andy McBrine (39) was followed by a stand of 94 alongside Campher (46).
Simi Singh’s brisk 30 took Ireland to 300-9 with Lockie Ferguson, Blair Tickner and Ish Sodhi each claiming two wickets.
New Zealand also made a faltering start to their innings with Will Young and Finn Allen dismissed to leave them on 19-2.
Martin Guptill (50) and Latham (23) steadied the Black Caps before Glenn Phillips added 38.
However, the Irish attack held the edge with Campher taking three wickets and they looked to be on course for a first win over world number one side New Zealand with the score on 218-7 and with less than 10 overs remaining.
But they were unable to keep Bracewell in check as he rattled along to keep the visitors in the hunt.
Mark Adair took a wicket and conceded just four runs from the penultimate over to leave New Zealand 281-9 with six balls remaining, before Bracewell’s late assault.
Bracewell’s unbeaten 127 from 82 balls proved decisive and the teams will meet again on Tuesday at Malahide in the second ODI, with the final match three days later.