New Zealand maintained their 100% winning record at the World Twenty20 with a dominant 75-run victory in Kolkata that sent Bangladesh home without a victory.

Already assured of a semi-final spot, the New Zealand bowlers produced another excellent display to defend 146 with ease and secure a fourth group two triumph.

Bangladesh soon slipped to 43 for six in reply and, after an 11-minute delay for floodlight failure, were dismissed for 70 inside 16 overs as Grant Elliott took three wickets for 12 runs from four overs and Ish Sodhi claimed 3-21.

The 20-year-old left-armer Mustafizur Rahman also excelled with the ball, outfoxing the New Zealand batsmen with his slower-ball cutters to return career-best Twenty20 international figures of five for 22.

New Zealand struggled to build on some early eye-catching strokeplay from Kane Williamson on a slow pitch showing signs of uneven bounce but managed to post 145 for eight.

Opening alongside Henry Nicholls after Martin Guptill was rested, Williamson took advantage of the new ball by striking four fours and a six during a 39-run powerplay.

Nicholls became the first victim for Mustafizur, missing a cutter, before a frustrated Williamson was bowled round his legs for 42 attempting a swipe off the left-armer.

Bangladesh then kept a lid on the scoring with Colin Munro and Ross Taylor struggling to get bat on ball until the former freed his arms in the 14th over. Having failed to hit a boundary in his first 25 balls, Munro blasted a four and two big sixes but was bowled attempting another off Al-Amin Hossain, while Corey Anderson and Taylor (28) also went.

Mustafizur, having had Grant Elliott caught off a leading edge, bowled Mitchell Santner and Nathan McCullum in consecutive deliveries. His hat-trick ball, the final delivery of the innings, was despatched for six by Mitchell McClenghan, who was among the wickets early.

McClenaghan bowled an advancing Mohammad Mithun, after Tamim Iqbal was run out by a brilliant Munro direct-hit from short third man, before Santner, McCullum, Sodhi and Elliott all struck to leave the Tigers reeling when the lights went out.

Mahmudullah became a T20I record ninth batsmen to be bowled in the match, failing to pick a Sodhi delivery, ahead of Elliott and Sodhi finishing the job.