A marauding 52-ball hundred from Colin Munro – his first in T20 internationals – powered New Zealand to a series win with a game to spare. Munro struck seven sixes and seven fours to lead the hosts to 195, which proved 47 too many for Bangladesh.
Bangladesh threatened briefly with a rapid 68-run stand between Soumya Sarkar and Sabbir Rahman, but lost their last seven wickets for 44 runs to be dismissed for 148 in 18.1 overs.
Bangladesh had started positively, though, after opting to bowl in Mount Maunganui. Their captain Mashrafe Mortaza struck with the first ball to remove Luke Ronchi, and then the spinners made further inroads to reduce New Zealand to 46 for 3 within six overs.
Munro took charge and added 123 runs – a New Zealand record for the fourth wicket in T20Is – with Tom Bruce, who helped himself to an unbeaten 59 off 39 balls, including five fours and a six.
Munro signalled his intent with a blast down the ground off Mashrafe in the first over. Despite the loss of Ronchi, Williamson, and Corey Anderson, Munro went on a boundary-hitting spree. He hit Rubel Hossain for back-to-back fours in the second over and then launched offspinning allrounder Mosaddek Hossain for two sixes in the eighth over.
Munro reached his fifty off 31 balls in the 11th over before hammering Shakib Al Hasan for a six over cover and four to long-on. He found excellent support from the newcomer Bruce, who rotated the strike well in addition to putting the bad balls away.
Munro hit top gear when he nailed Mahmudullah behind square for two sixes in three balls in the 13th over. Mahmudullah eventually conceded 28 runs off that over as Munro zoomed from 64 to 92.
He brought up his century with a quick single in the 16th over, becoming the third New Zealander, after Brendon McCullum and Martin Guptill, to score a T20I hundred.