New Zealand followed their thrilling three-run victory on Wednesday night with an impressive all-round display, following the disappointment of a 2-0 Test series defeat.
The tourists won the toss and piled on 170 with Jesse Ryder scoring a 37-ball 52 that included three huge sixes. Brendon McCullum scored 49 from 34 balls.
Sri Lanka's bowlers, with the exception of spinners Ajantha Mendis (1-21) and Sanath Jayasuriya (2-22), were punished as Ryder and McCullum gave New Zealand a winning platform with an 84-run opening stand.
Sri Lanka made a poor start to their run chase, collapsing to 11 for 3 with Tillakaratne Dilshan (one), Mahela Udawatte (nought) and Jayasuriya (seven) all going early.
Mahela Jayawardene and Kumar Sangakkara repaired some of the damage with a 67-run partnership.
Jayawardene stroked 41 from 30 balls, with five fours and a six, and Sangakkara cracked a career-best 69 from 50 balls with seven boundaries.
However, the hosts were always behind the run rate as New Zealand bowled tightly and fielded brilliantly throughout the innings.
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