Shakib Al Hasan bagged four wickets to set up Bangladesh's consolation eight-wicket victory over the West Indies in the third and final one-day international on Tuesday.
The tourists were dismissed for their second-lowest total of 61 after being put in to bat, with left-arm spinner Shakib finishing with a career-best 4-16 off five disciplined overs.
The West Indies' lowest total in one-day internationals was 54 against South Africa in Cape Town in 2004.
Bangladesh, who had lost the first two one-dayers, achieved the small target with 30 overs to spare. Opener Tamim Iqbal top-scored with an unbeaten 36.
"There was nothing to lose today and the boys came out and showed character," said Bangladesh skipper Mushfiqur Rahim, whose side will now play a two-Test series starting in Chittagong on October 21.
"This is a big lift before the Test series. The pacemen bowled well and were backed by the spinners. Hopefully, we will keep winning in Chittagong."
The West Indies earlier lost their last nine wickets for 28 runs in a dramatic collapse, with man-of-the-match Shakib, off-spinner Nasir Hossain (2-3) and paceman Shafiul Islam (2-21) doing the maximum damage.
Opener Kieran Powell (25) and debutant Carlos Brathwaite (11) were the only batsmen to reach double figures in West Indies' dismal batting performance.
"We took our foot off the gas today," said West Indies captain Darren Sammy.
"It is a good feeling (to win the series), but today shows you can never take your opponents lightly. We have seen what Bangladesh can do at home and hope to start the Test series on a high."
The West Indies, who had dismissed Bangladesh for 58 in a World Cup match in Dhaka in March, were at the receiving end this time as their innings lasted just 22 overs.
Their batting woes began in the 11th over when Shafiul had in-form Marlon Samuels caught by Suhrawadi Shuvo in the covers for his first victim. Samuels, who scored half-centuries in the last two one-dayers, could make just five.
Nasir, wicketless in his six one-dayers before this match, was on hat-trick when he bowled Powell and then held a return catch to dismiss hard-hitting Kieron Pollard off successive deliveries.
The West Indies made three changes from the side that won the second one-dayer by eight wickets in Dhaka last week.
Powell, Anthony Martin and Brathwaite came in place of Devendra Bishoo, Ravi Rampaul and Lendl Simmons.
Bangladesh replaced Mohammad Ashraful, Alok Kapali, Abdur Razzak and Rubel Hossain with Shuvo, Shuvagata Hom, Shahriar Nafees and Nazmul Hossain.
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