Sparkling centuries by Paul Stirling and Harry Tector proved, agonisingly, not enough for Ireland as they were denied a famous first triumph over New Zealand, suffering an agonising one-run defeat in Dublin.
Martin Guptill's thumping hundred for the visitors helped the Black Caps amass an imposing 6-360 from their 50 overs on Friday and enable them to sweep the one-day international series 3-0.
But it wasn't easy at Malahide. Stirling and Tector had other ideas for Ireland with a magnificent stand, but when the latter departed with more than 50 runs required, the chase looked dead and buried.
Ireland's lower order, though, continued to swing hard and brought the equation down to 10 off the last over, but Blair Tickner held his nerve to deny the hosts, despite the Irish scoring their highest ever ODI total.
Guptill did the early damage and scored his 18th century for New Zealand in the format before he went for 115.
Henry Nicholls had already picked up the baton by this point and smashed three maximums in his 54-ball 79 to help the tourists set 361 for victory.
A record third-wicket partnership between Stirling and Tector, though, ensured Ireland made a strong fist of the reply.
Opener Stirling reached three figures with a boundary down to third man but was furious when he exited for 120 after becoming one of Matt Henry's four victims.
The 179-run partnership for the third-wicket with Tector set a new record for Ireland in ODIs and the number four continued in impressive fashion with five maximums and was able to bring up a second century of the series.
When Tector went for 108, the hosts' hopes of victory looked slim but George Dockrell's rapid 22 kept them in the fight only for New Zealand to hold their nerve and eventually restrict them to 9-359.
It secured the Black Caps a 3-0 series win ahead of three Twenty20 internationals beginning on Monday.