Defending a total of 146 for seven, the visitors seemed destined to fall to the mighty hitting of Rovman Powell as the home skipper blazed 60 off 35 balls with five fours and four sixes to lift his side from the depths of 61 for seven in the 12th over to within touching distance of a sensational victory.
His eighth-wicket partnership of 68 off 38 balls with fellow all-rounder Romario Shepherd (22) looked to have swung the match decisively his team's way as, despite the loss of Shepherd in the 19th over, Powell was still at the crease in partnership with Alzarri Joseph with nine runs needed for victory when Mahmud started the final over.
However, the seamer responded to the challenge magnificently, having Powell caught behind by Bangladesh captain Litton Das off the third ball of the over and then uprooting Joseph’s middle-stump two balls later to leave local hero Obed McCoy a helpless spectator at the other end.
McCoy had earlier claimed his 50th wicket in T20 Internationals on his return to the West Indies team, finishing with figures of two for 30.
Left-arm spinner Akeal Hosein was again at his miserly best in taking two for 13 off his four overs but Bangladesh were able to gain late impetus from 96 for five in the 15th over courtesy of Jaker Ali, Shamim Hosein and Mahedi Hasan.
Opener Soumya Sarkar held the early part of the innings together with a topscore of 43.
Hasan then followed his unbeaten 26 with an outstanding bowling effort, his spin varieties earning him four for 13, and subsequently the "Man of the Match" award, as the West Indies middle-order caved in for what looked like an inevitable massive defeat.
Powell and Shepherd nearly completed a memorable rescue act, though, before they were thwarted by the excellent Mahmud.
