A knock of 102 from Martin Guptill helped New Zealand to overcome Sri Lanka by 36 runs at the Bay Oval and also wrap up the one-day international series between the two sides by a 3-1 margin.
The Kiwis batted first on home soil and - spearheaded by opener Guptill as he scored his 10th ODI century - they went on to post 294-5 from their 50 overs.
Kane Williamson and Ross Taylor also made useful contributions, having both put 61 runs apiece on the board.
In reply, touring Sri Lanka lost their opening three batsmen Danushka Gunathilaka, Tillakaratne Dilshan and Lahiru Thirimanne for a combined 20 runs.
Their pursuit of the 295-run victory target was then somewhat steadied by Angelo Mathews, but when he fell to the bowling of Mark Henry five runs short of his century, Sri Lanka's challenge wilted.
The wicket of Mathews was one of five that 24-year-old Henry claimed, which earned him the Man of the Match award.
The teams will now meet in a Twenty20 encounter at the same venue on Thursday.
