Bangladesh captain Mashrafe Mortaza won the toss and elected to bat in the first Twenty20 global against New Zealand at Napier on Tuesday.
Bangladesh's tally owed itself to a half-century from Mahmudullah, batting at No. 6. Chasing a modest 142 to win, New Zealand went past Bangladesh's target without many qualms.
There was only a brief respite for Bangladesh before T20 debutant Ben Wheeler picked up the first of his two wickets and had Tamim Iqbal caught by Tom Bruce on the boundary. Out of the three, only Bruce failed to impress as the two bowlers shared 5 wickets between them to wreck the Bangladeshi batting order.
Ferguson finished with figures of 3 for 32 but the rearguard action had given Bangladesh something to bowl at.
Player of the match Williamson hit five fours and two sixes in his match-winning innings while Grandhomme blasted three fours and three sixes in a 22-ball 41.
Guptill pulled a hamstring while running between the wickets in Saturday's third one-day global, which New Zealand won by eight wickets, and could be sidelined for up to four weeks.
But the game narrowed with batsmen Neil Broom, Colin Munro, Corey Anderson and Tom Bruce all dismissed for low totals.
With the score reading 62-4 after 11 overs, Williamson was joined by de Grandhomme, and the latter provided solid support to his skipper.
The Black Caps skipper scored 73 for the hosts at McLean Park in Napier to take the first T20 against Bangladesh and also man-of-the-match honours. Bangladesh are having a torrid time in New Zealand already, since they were blanked 0-3 in the ODI series earlier on the first leg of their tour.
Ferguson is only the second bowler after Australia's Michael Kasprowicz to take two wickets with his first two deliveries in a Twenty20 global: Kasprowicz achieved the feat in the first-ever Twenty20 worldwide between New Zealand and Australia in 2005. The Bangladesh all-rounder then realised that he was too close to the boundary cushion and tossed the ball back in the field.