Bangladesh beat England in final T20 to complete clean sweep
Chasing 159 to win thanks to a 57-ball 73 by Das and an unbeaten 47 by Najmul Hossain Shanto, England lost Phil Salt for a first-ball duck in debutant Tanvir Islam's opening over before Dawid Malan (53) and Jos Buttler (40) steadied the ship.
Malan then top-edged one to Das behind the wickets to become Mustafizur Rahman's 100th victim in the 14th over before Buttler was run out next ball attempting a risky single as the hosts heaped the pressure on England.
Moeen Ali and Ben Duckett also perished attempting big shots against Taskin Ahmed and the visitors never recovered, finishing on 142-6 from their 20 overs.
It is only the third time that England have been blanked in a bilateral T20 series featuring at least two matches.
"We were really good in this series. I thought we fielded exceptionally," said Bangladesh skipper Shakib Al Hasan.
"That has been one of the major changes. If we look at the World Cup next year, we can build from here."
Bangladesh had denied England a clean sweep in the preceding three-match one-day international series by winning the final game, and they produced some commanding displays against the world champions in the shortest format.
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Having stunned England in the opening two T20 matches, they got off to a solid start after being asked to bat by Buttler as Das and fellow opener Rony Talukdar (24) settled in early on a good wicket to score 46 in the powerplay.
Talukdar failed to make the most of being dropped on 17 by Rehan Ahmed off Jofra Archer and was caught following a miscued reverse-sweep off Adil Rashid. But his replacement Shanto then came to the crease and further frustrated England.
Das was also handed a reprieve, dropped by Duckett at deep midwicket off Archer after he made his ninth half-century, and he went on to punish England's bowlers before finally holing out to Salt in the deep.
Shanto narrowly missed out on his half-century as England clamped down in the final overs with Rashid (1-23), Chris Jordan (1-21) and Sam Curran (0-28) leading the way.
"Really disappointed but congratulations to Bangladesh. They deserved their victory," Buttler said.
"We came back well and missed some opportunities in the field which is disappointing in this game. It was a good score to restrict them to but that didn't happen.
"It's really poor and I'm really disappointed in myself for not diving in the field, it cost us the game."
