In a match shortened by rain to 43 overs per side in Sylhet, the hosts posted 322-3 in Mortaza's final game as skipper, with Das and Iqbal sharing a 292-run opening stand – the third highest in ODI history.
Zimbabwe were set a revised target of 342 and came up well short, Mortaza earning his 50th win in the format as the side's leader, the 36-year-old chipping in with 1-47 in a 123-run DLS triumph.
The home side were making fine headway when the weather closed in, the Tigers going off for more than two and a half hours with 182 runs on the board and the first pairing still going strong.
After resuming, Carl Mumba did manage to break the bond, taking three late wickets, although Tamim – who made 158 in the second match – remained unbeaten on 128.
Das smashed 16 fours and eight sixes in his stunning career-best 176, which came from 143 deliveries and ensured he eclipsed Tamim's tally from the previous outing to claim a national record in the format.
Zimbabwe's response was not nearly as spectacular, with Tinashe Kamunhukamwe falling in the first over to Mortaza and setting the tone for an innings of fruitless toil from the tourists.
Sikandar Raza did post a defiant 61, with Regis Chakabva (34) and Wesley Madhevere (42) also gaining some credit, but their contributions came in another losing effort as Mohammad Saifuddin (4-41) did most of the damage.
The result completed a miserable series for Zimbabwe, who lost the opener by a record 169 runs, before succumbing to a defeat by just four runs in the second meeting.
In all honesty, few are likely to favour the team’s chances against a full-strength Bangladesh when the tour bowls off later this month. The West Indies were left short-handed in the experience department after 12 of their first-string players opted out of the tour after listing health and safety concerns.
As a result of the regulars opting out, the selectors were forced to hastily assembly a squad that consisted of majority fringe players and a few others with limited experience. Bangladesh outplayed the full-strength team during a 2018 tour, and have generally had the better of the results in recent encounters.
Still, Mohammed refuses to completely write off the team’s chances before a ball is bowled and was grateful to receive encouragement from the well-respected former West Indies captain, Lloyd, who reportedly penned letters to several players.
“It meant a lot coming from one of our greats. Those are the things you want to hear because there has been a lot of negative talk going around,” Mohammed told members of the media on Thursday, via an online press conference from Bangladesh.
“When you hear from someone like Clive Lloyd it puts great belief within you. With the World Cup coming up it’s an opportunity for all of us to put our hands up and try and get into the original team, when the full squad is back and have a chance of going to the World Cup. I think it inspired the guys a lot and hopefully, we can back his words up.”
Louis, playing with patience and determination, was dismissed for 97 after spending 27 balls in the nineties. He charged at Bangladesh’s stand-in captain and spinner Mehidy Hasan Miraz but was caught at slip by Shahadat Hossain. Athanaze, who had been steadily accelerating, fell three overs later for 90, edging Taijul Islam behind. It marked the second time in Athanaze’s brief Test career that he had been dismissed in the nineties.
The pair’s stand was the backbone of the West Indies innings, revitalizing the side after early setbacks. Captain Kraigg Brathwaite fell for 4, trapped lbw by Taskin Ahmed, and Keacy Carty departed soon after for a duck, caught at mid-on trying to flick Taskin. At 12-2, the West Indies were under pressure until Louis and Kavem Hodge steadied the ship.
Hodge, who made 25, was run out after a brilliant throw from Taijul Islam at long leg. His dismissal brought Athanaze to the crease, and together with Louis, he set about rebuilding and eventually dominating the Bangladesh bowling attack.
Louis reached his half-century with a straight drive off Taskin, showcasing his ability to punish loose deliveries amidst a largely cautious approach. Athanaze took a more aggressive route, particularly in the final session, finding the boundary with sweeps, reverse sweeps, and cuts as he raised the scoring rate.
Louis’s innings included nine boundaries and a six, while Athanaze struck 12 fours and a six. Their contrasting styles complemented each other, as they added 140 runs at a brisk pace, frustrating Bangladesh’s bowlers, who had earlier kept the scoring rate in check.
After their departures, Justin Greaves and Joshua Da Silva stabilized the innings against the second new ball. Greaves ended the day unbeaten, with Da Silva scoring freely in the closing overs before bad light and a drizzle brought an early end to proceedings after 84 overs.
Bangladesh’s bowlers struggled to capitalize on the early breakthroughs. Taskin Ahmed was the pick of the attack with figures of 2-46, while Mehidy Hasan Miraz (1-45) and Taijul Islam (1-56) provided moments of control but lacked consistency. The fielding unit also let opportunities slip, including a dropped catch off Louis when he was in the nineties.
The West Indies will resume on day two with five wickets in hand and an opportunity to push toward a commanding first-innings total. Bangladesh will look to capitalize on the breakthroughs late on day one and restrict the hosts in the morning session.
For the West Indies, the day belonged to Louis and Athanaze, whose near-centuries not only steadied the innings but also put the team in a strong position as they aim to set the tone in the series.
Bangladesh declared in Chattogram to set the Windies a target of 395, which seemed improbable when Mayers arrived at the crease, batting at number five and joining the fray at 59-3.
But the new man, who made 40 in his first innings, joined Nkrumah Bonner to put on 216 for the next wicket and swing momentum back in the tourists' favour on Sunday.
Mayers later did the heavy lifting in another three-figure partnership with Joshua Da Silva, too, and was fittingly the man to scramble the match-winning single with 15 balls remaining in the first Test - and three wickets to spare.
His stunning display sealed the fifth-highest successful chase in the history of the format, a new benchmark in Asia and the best anywhere since 2008.
Mayers survived 310 balls in 415 minutes as he scored 20 fours and seven sixes.
"I have a few centuries in domestic cricket, but this is very special to me," the 28-year-old said.
"It's my highest score and the longest I've ever batted in first-class cricket. It's very special to me to get a double in my first Test match."
Mayers became just the sixth batsman to score a double century on his Test debut and the sixth to pass 200 in a fourth innings.
Only Mayers has combined the two and recorded a double hundred in the fourth innings of his bow in the longest format.
Mayers - with just five limited-overs internationals to his name, his highest score 40 - was driven by the team's need to break new ground on day five, although he tried not to be distracted by a scoreboard that increasingly read in the Windies' favour.
"Truly, I was not looking at the target," he said.
"I was just trying to stick to my game plan for as long as possible, try not to look at the scoreboard, try to bat as long as possible and know within myself that, if I bat the whole day, my team will come across the line.
"The hundred was on the cards for me personally, yes, but I knew the team needed me to score more than 100.
"Batting, I was always thinking of scoring 150 - I thought, at the beginning of the day, if I score 150, 160, my team will be in good stead to cross the line.
"But as I reached 160, I knew that I had to push more and it just encouraged me to go further."
The tourists were all out for only 186 at the start of a three-match series, KL Rahul top scoring with 73 from 70 balls in Mirpur on Sunday, Shakib Al Hasan taking 5-36 and Ebadot Hossain 4-47.
Bangladesh looked to have blown their chance to take a 1-0 lead when they lost five wickets for just eight runs, slumping to 136-9.
But Mehidy came to the rescue, dominating an unbroken 10th-wicket stand of 51 with Mustafizur Rahman with a brilliant 38 not out to give the Tigers the most unlikely of victories and spark jubilant scenes in Dhaka.
Shakib had earlier played a huge role, dismissing Rohit Sharma (27) and Virat Kohli (nine) in the 11th over after Shikhar Dhawan fell cheaply.
Rahul, coming in at number five, and Shreyas Iyer (24) put on 60 for the fifth wicket before India lost four wickets for as many runs, Shakib and Ebadot doing the damage.
There were four sixes from Rahul, taking over as wicketkeeper-batter with Rishabh Pant ruled out, in an excellent knock that looked to be decisive as the Tigers capitulated in the run chase.
Stand-in captain Litton Das top scored with 41 after Deepak Chahar removed Najmul Hossain Shanto with the first ball of Bangladesh's innings, and Shakib made 29.
Mohammed Siraj took 3-32 and debutant Kuldeep Sen 2-37 as the Tigers wilted, but Mehidy was dropped by Rahul on 15 and made him pay, sealing a sensational victory with four overs to spare with great support from Mustafizur (10no)
Shakib and Ebadot tear through India
Shakib gave yet another demonstration of how he has risen to the top of the ODI and T20I all-rounder rankings, claiming his fourth five-wicket haul in the 50-over format.
He claimed the huge scalps of Rohit and Kohli in the 11th over, bowling his spin with great guile. Ebadot was the pick of the pacemen in his second ODI, sparking a collapse by dismissing Washington Sundar and also claiming the scalp of Rahul.
Magical Mehidy completes great escape
The crowd had been silenced and Bangladesh were on the ropes at 136-9 when Siraj trapped Hasan Mahmud leg before.
Step forward Mehidy, who struck two sixes and another four boundaries in a brilliant 72-ball knock after coming in at number eight, showing nerves of steel as he kept the strike and Mustafizur also remained calm under pressure in the Tigers' second-highest 10th-wicket ODI stand.
Bangladesh have now won 12 of their past 14 ODIs, ending a run of five consecutive losses to India in this format.
The Proteas were bowled out for 204 in their second innings in Durban on Sunday, setting the tourists 274 to win.
Captain Dean Elgar top-scored with 64, while debutant Ryan Rickelton complied an unbeaten 39 as wickets tumbled at the other end.
Ebadot Hossain (3-40), Mehidy Hasan (3-85) and Taskin Ahmed (2-24) were the Tigers' wicket-takers on the penultimate day, but their hopes of taking a 1-0 lead in the two-match series appear to be slim after they were reduced to 11-3 before bad light brought play to an early end.
Mahmudul Hasan Joy and Mominul Haque were dismissed by Maharaj (2-7) after Harmer removed Shadman Islam, leaving South Africa needing seven wickets for victory on the final day.
Ebadot snared Sarel Erwee leg before after the Proteas resumed on 6-0, but Bangladesh let Elgar off the hook twice before he brought up a 21st Test half-century.
Najmul Hossain Shanto and Yasir Ali dropped the skipper in the slips and Keegan Petersen was fortunate that Mominul opted against reviewing when he was struck in front on 14 by Khaled Ahmed, as umpire Marais Erasmus kept his finger down.
Elgar fell lbw to Taskin after lunch and Petersen (36) was dismissed by Mehidy before Temba Bavuma fell for only four.
Rickelton played patiently to keep the lead building as South Africa lost their last six wickets for 56 runs. Maharaj and Harmer then spun South Africa well on course for victory before bad light prevented them from making further inroads.
Elgar rides his luck
Skipper Elgar was grateful for some sloppy work in the slips from Yasir and Shanto, taking advantage of those strokes of luck to spend almost three hours at the crease to strengthen South Africa's grip on the game.
Rickelton struck four boundaries but was denied a debut half-century when he ran out of partners.
Tigers in a spin
The tourists surely needed a solid start to their second innings to have any chance of pulling off a victory, but they were rocked when Shadman was caught by Petersen at slip off Harmer's second ball.
Things went from bad to worse for Bangladesh when left-arm tweaker Maharaj struck twice in an over, bowling first-innings centurion Joy and pinning Mominul in front.
Bangladesh resumed at 139-5 on the third day of the second Test, but an efficient Proteas attack picked up where they left off on day two with the ball, dismissing the tourists for just 78 further runs.
The hosts declared at 176-6 in their second innings after Sarel Erwee (41) and Kyle Verreynne (39 not out) helped them to a 412-run lead, before removing Tamim Iqbal, Mahmudul Hasan Joy, and Najmul Hossain Shanto in quick fashion to put themselves on the brink of a 2-0 triumph.
Bangladesh managed to hold off the Proteas attack for much of the morning, reaching 192 without any further losses through the efforts of Yasir Ali (46) and Mushfiqur Rahim (51), but Maharaj's dismissal of Ali was the catalyst for a fine display of bowling from the hosts.
One day after producing the best batting performance of his Test career to drag South Africa to 453 in their first innings, Maharaj removed Mehidy Hasan Miraz (11), while Harmer dismissed Mushfiqur, Taijul Islam (five), and Ebadot Hossain, the last of the trio for nought.
The hosts went in search of quick runs when they picked up the bat, reaching 60 before captain Dean Elgar was dismissed by Taijul for 26.
Erwee, Verreynne and Bavuma (30) then posted decent returns to set the tourists a mammoth target, before Elgar declared in hope of a rapid victory.
Bangladesh's second attempt with the bat began in even worse fashion than their first, with Hasan Joy caught by Wiaan Mulder from Maharaj's first ball.
Maharaj and Harmer claimed another wicket apiece before the day was through, with the former sending Hossain Shanto for just seven runs and Harmer dismissing Iqbal for 13.
The hosts now appear certain to clinch the series on day four, with the below-par tourists needing 386 to level the series.
Maharaj superb once more
Having recorded just his fourth Test half-century to put South Africa in a commanding position on day two, the 32-year-old spinner starred in more typical fashion on day three.
He set the home attack on their way by adding two more first-innings wickets, before claiming two dismissals for just 17 runs as the visitors saw their top order decimated later in the day.
Harmer gets in on the act
Harmer was also outstanding with the ball, claiming the other three wickets at the end of Bangladesh's first innings before wrapping up a fine day's work by dismissing Tamim.
Hoping to secure a 2-0 victory in the two-match series, South Africa resumed on 278-5, but an excellent all-round performance from the hosts in Port Elizabeth ensured they ended day two in a dominant position.
Maharaj's efficient 84 helped South Africa reach 453 all out, then Wiaan Mulder did the bulk of the damage with the ball as Bangladesh slumped to 139-5 in reply, trailing by 314 runs.
The tourists' hopes of avoiding the follow-on would appear to rest with Mushfiqur Rahim, who survived until stumps on 30 not out.
There were only 22 runs added to South Africa's overnight total before Kyle Verreynne was bowled by Khaled Ahmed.
But any hopes of Bangladesh quickly working through the South Africa tail were soon subverted by Maharaj, who hit nine fours and three sixes in a superb innings, his half-century coming in 50 balls.
Taijul Islam removed him either side of claiming the dismissals of Mulder (33) and Simon Harmer (29) to finish with figures of 6-135.
Having made a solid contribution with the bat, Mulder trapped Tamim Iqbal and Najmul Hossain Shanto lbw two overs apart, that duo having compiled a partnership of 79 to move Bangladesh to 82-1.
Captain Mominul Haque (six) fell in the same fashion to Mulder, and Duanne Olivier, who earlier dismissed Mahmudal Hasan Joy for a duck, knocked over Litton Das' middle stump to leave Bangladesh five down and in a dismal mess.
Maharaj magic
A half-century for Maharaj was his fourth in Test cricket and his first since December 2020. A mistimed and perhaps overaggressive attempt at a sweep to leg side saw Taijul deny him his first Test hundred.
Mulder shows all-round ability
After scoring valuable runs in a seventh-wicket stand of 80 with Maharaj, all-rounder Mulder tilted the contest decidedly in South Africa's favour with the ball. He ended the day with figures of 3-15, eyeing his first Test five-for.
The Proteas were bowled out for 204 in their second innings in Durban on Sunday, setting the tourists 274 to win before Maharaj and Simon Harmer reduced Bangladesh to 11-3 at stumps.
The visitors' sizeable task significantly increased when they lost Mushfiqur Rahim in the first over the day, pinned in front by Maharaj, who claimed six of the seven wickets to fall on Monday to finish with 7-32.
Dean Elgar's hosts only used spinners Harmer (3-21) and Maharaj in the final innings, which lasted just 19 overs in total, as they claimed a 1-0 lead in the two-match series by bowling the Tigers out for 53.
The rampant Maharaj picked up where he left off on day four as he struck with his fifth delivery to remove Mushfiqur for a duck, while Litton Das (two) chipped a simple catch to Harmer in the left-armer's next over.
Yasir Ali (five), who was bowled by Maharaj, and Mehidy Hasan Miraz (zero) followed in quick succession, with the latter snaffled at slip by Keegan Petersen off Harmer.
Najmul Hossain Shanto offered brief resistance but when he was stumped for 26 by Kyle Verreynne off Harmer, Bangladesh were languishing at 50-8 and Maharaj soon wrapped up victory.
Khaled Ahmed needlessly slogged the finger spinner to Lizaad Williams before Taskin Ahmed (14), who survived an earlier lbw review, edged Maharaj to Wiaan Mulder at slip to seal victory in just 55 minutes.
Spin tames Tigers
Maharaj went wicketless in 37 overs in the first innings. However, he ramped up the pressure in the second with his seven dismissals coming in 60 balls, the second-fastest since 2002 after Stuart Broad's against Australia in 2015, as he collected his eighth Test five-for and best figures at home.
Indeed, it was also the first time South Africa have bowled out an opposition using only two bowlers after neither of the seamers, Duanne Olivier and Williams, were called on in the second innings.
Kingsmead hoodoo ends in dominant fashion
South Africa cruised to just their second win in their last 10 matches at Kingsmead as Bangladesh were bowled out for their second-lowest total in Tests and lowest against the Proteas.
The visitors will have to figure out how to bounce back against Maharaj and Harmer, who took seven wickets on his comeback to international cricket, in the final Test in Port Elizabeth that starts on Thursday.
Left-arm spinner Maharaj bamboozled the Tigers to dismiss them for just 53 in the opener, picking up 7-32, and he repeated the trick in Port Elizabeth with figures of 7-40 in the second innings.
Simon Harmer (3-34) again provided capable support as the Proteas utilised just the two spinners to secure the series in 23.3 overs and move to second in the World Test Championship table.
The spin pair left Bangladesh reeling at 27-3 overnight and picked up where they left off on Monday but not before there was an international cricketing first.
Khaya Zondo, who made his Test debut, and Glenton Stuurman replaced Sarel Erwee and Wiaan Mulder as COVID-19 substitutes – a first instance of the protocol being used in international cricket.
Once play started with the substitute duo on the field, Maharaj soon had both Mominul Haque (five) and Mushfiqur Rahim (one) caught.
Yasir Ali fell to a similar Harmer trap as he holed out to deep midwicket for nought, before Kyle Verreyne stumped top scorer Litton Das (27) to complete Maharaj's five-for.
Verreyne and Maharaj combined again to remove Mehidy Hasan Miraz for 20, caught behind on review, and the left-armer pinned Khaled Ahmed in front without scoring shortly after.
Harmer then trapped Taijul Islam for a duck three balls later to wrap up victory within an hour on the morning session of day four.
Magical Maharaj
Maharaj raced to a quickfire 84 in the first innings to go along with his two dismissals, but again the 32-year-old came alive in the second innings as he reached 150 dismissals in Test cricket.
He toyed with the Bangladesh batters' minds, uncertain whether the ball would spin or go straight on, as he collected another seven-wicket haul to take him to a series-leading 16 wickets overall.
Fierce Proteas tame Tigers
Bangladesh may not have collapsed for just 53 this time, but it was hardly better as the Tigers looked stunned by Maharaj and Harmer and they have now not beaten the Proteas in 14 red-ball attempts.
Meanwhile, South Africa have won five of their last six Tests, including their last three in a row for the first time since a three-game span between December 2018 to January 2019.
Given a target of 185 for the victory, the visitors cruised to 42 without loss after seven overs before bad light and subsequent rain halted proceedings at the Rawalpindi Cricket Stadium.
After starting the day 9-2, Pakistan saw Saim Ayub removed by Taskin Ahmed (1-40) before Rana ripped through the hosts' batting order, claiming the wickets of Shan Masood (28), Babar Azam (11) and Saud Shakeel (two) in four overs.
Mohammad Rizwan's 43 from 73 deliveries threatened to bring Pakistan back into the contest, only for Mahmud to claim successive wickets in the 36th over before removing Mir Hamza (four) to conclude a dominant session for Bangladesh.
Zakir Hasan and Shadman Islam wasted no time in setting a swift pace in the chase, with the former striking 31 runs from the 23 balls he faced, including two sixes and two fours before the weather closed in.
The pair will return to the crease on Tuesday needing 143 runs for a memorable series victory.
Data Debrief: Rana and Mahmud roar Tigers close
Rana's figures of 4-44 were his best for Bangladesh, with their bowling display the first time in the tourists' Test history that all ten wickets were picked up by fast bowlers.
Mahmud also impressed, claiming his first five-wicket haul in just his third Test outing for Bangladesh.
Bad light brought a slightly premature conclusion to proceedings on day three, with South Africa 75 runs ahead having bowled Bangladesh out for 298 and started their second innings 6-0.
But this was a day for the Tigers and opener Mahmudul (137) to reflect fondly on in Durban.
Mahmudul had been their one shining light on day two in only his third Test, unbeaten on 44 at stumps with his team a concerning 98-4 in reply to the Proteas' 367.
Nightwatchman Taskin Ahmed departed in only the third over of Saturday's play, but Mahmudul finally found a team-mate able to stick around in Liton Das and the pair put on 82 for the sixth wicket.
Mahmudul was dropped by Sarel Erwee on 64 and reached 90 before he inadvertently had partner Yasir Ali – the next man in after Liton – ran out.
A landmark century kept Bangladesh moving, though, and their innings only ended when Mahmudul's did, with the 31-year-old not quite able to carry his bat after playing with greater ambition alongside the tail, caught by Simon Harmer at slip.
Marvellous Mahmudul makes history
The previous high score from a Bangladesh batsman against South Africa had been Mominul Haque's 77 in 2017, a mark Mahmudul cleared by some distance.
He survived 326 balls and almost seven and a half hours, scoring 15 fours and a pair of sixes. Six of those boundaries came across two overs after Mehidy Hasan Miraz departed late in the innings.
No first five-fer for Harmer
South Africa remain in control of the Test match, but they allowed Bangladesh to retain some hope by failing to follow up their superb early bowling from the previous day.
Harmer finished Friday with outstanding bowling figures of 4-42 from 20 overs, yet he allowed 61 runs for no wickets from his next 20, improbably unable to claim a first five-fer. At least he had his day two efforts to fall back on; Keshav Maharaj finished on 0-65.
The hosts struggled after electing to bat first, setting a target of just 210, but England's response for a while looked in danger of falling short.
Malan picked up the pace following a considered start, however, eventually finishing on 114 not out to reach 212-7 and brilliantly drag England over the line.
Tamim Iqbal (23) began purposefully but Bangladesh soon had their momentum disrupted by Mark Wood (2-34) and Chris Woakes (1-28), the former dismissing the hosts' captain with an emphatic delivery.
The spinners then took care of Bangladesh's middle order, with each England bowler claiming at least one wicket.
Najmul Hossain Shanto (58) proved the biggest nuisance, his maiden half-century crucial in helping the hosts surpass 200.
But a tremendous catch from Jason Roy sent him back to the pavilion at 159-5 in what proved a turning point – Bangladesh added only another 50 runs.
England's chase received an early blow when Roy (4) fell to a simple Iqbal catch in the first over, while Phil Salt (12), James Vince (6) and Jos Buttler (9) were not much better.
Taijul Islam (3-54) took two of the first four wickets as England found themselves on 65-4, but amid all the floundering, Malan was calmly plugging away.
A close escape from an lbw appeal in the 22nd over proved vital, with Malan first playing it steady as he reached 50 off 92, before then getting his century off 134.
He secured the ton with a clip through midwicket that brought up his 10th boundary, and another four – whacked through wide mid-on – fittingly ensured Malan clinched victory.
Malan's the man of the moment
England's bowlers did some sterling work early on, with Jofra Archer, Wood, Moeen Ali and Adil Rashid all taking two wickets each, but the generally disappointing nature of the visitors' chase meant Malan had to take on the role of firefighter.
After looking all at sea at 65-4, Malan took charge. In claiming his 100, he becomes the second-fastest player to four ODI centuries.
Taijul gave Bangladesh a chance
Bangladesh were also largely better with the ball than the bat. Taijul was the pick of the bunch for the hosts, taking three wickets – more than anyone else in the match.
His efforts were central to England getting off to a stuttering start. In the end, one man's class was the difference, and to be fair to Bangladesh, Malan looked like he could bat another 50 overs and still not get removed.
Chasing 194 for victory, Bangladesh scored 158-6 off their 20 overs.
Shakib al Hasan’s unbeaten 68 took the tourists close but the West Indies bowlers were always on top, notwithstanding a few big overs for Bangladesh near the end.
Romario Shepherd took 2-38 and Obed McCoy, who took wickets with the first two balls he bowled in the match, returned figures of 2-37, 20 of them conceded in the 19th over of the match.
Shakib, who during the match, became the only batsman to score 2000 runs and take more than 100 wickets in T20 history, featured in partnerships of 53 with Afif Hossain who scored 34 from 27 balls. The latter was dismissed as the visitors slumped to 78-4 in the 11th over.
Shakib and Mossadek Hossain added another 53 for the sixth wicket but with the required run rate steadily climbing, Bangladesh’s chances of victory seemed remote.
The West Indies won the toss and chose to bat, scoring 193-5 from their 50 overs.
Brandon King scored 50 as the West Indies sought to take a 1-0 lead in the three-match series after the first match on Saturday ended in a no-result because of rain.
After losing Shamarh Brooks for a duck and Kyle Mayers for 17, King and Captain Nicholas Pooran shared in a third-wicket stand of 74.
Pooran smashed three fours and a six in his 30-ball 34 before he was trapped lbw by Mossadek Hossain. His departure saw the arrival of his vice-captain, who after a tentative start exploded against the Bangladesh attack.
Powell and King shared in a 63-run fourth-wicket partnership from just 29 balls when King whose 50 came up off 36 balls with six fours and a six, got out caught by Shakib Al Hasan trying to hit Shoriful Islam over the boundary.
Powell, meantime, showed little mercy racing to 50 from 20 balls. Twenty-three of those runs came in the 16 over when he hit Shakib for three sixes and a four. He remained unbeaten on 61 from just 28 balls. He hit two fours and six sixes, the last of which came from the last ball of the innings when he clubbed Shoriful over the deep midwicket boundary.
Romario Shepherd made three and was replaced by Odean Smith, who hit the third ball of the final over to end unbeaten on 11 from just four balls.
Shoriful returned figures of 2-40 while there was a wicket each for Shakib (1-38), Mahedi Hasan (1-31) and Mossadek (1-0).
The Proteas looked to be heading for their first loss in Group D when they toiled to 113-6 in Long Island, but some slow scoring from Bangladesh left the match in the balance late on.
Requiring seven runs from the final three balls for victory, Bangladesh saw both Jaker Ali and Mahmudullah caught by Markram, who was in the right place at the right time on the boundary as South Africa's opponents went in search of a maximum.
The result keeps South Africa top of Group D and on course for a Super-8 berth with six points, four clear of Bangladesh, but Markram acknowledged they had been lucky.
"You're always pretty nervous in the final over in a game like that. It was always on a knife's edge, it can make you mentally tired," he said after the match.
"It's always nice to be in them though. Sometimes you get on the right side of it, sometimes not, but it's very entertaining.
"That 19.5 full toss could've gone anywhere, it could've gone two more metres further and we'd have had a different conversation.
"A few things went our way today, we were very fortunate to get on the right side.
"Today was one of those days where the seamers were bowling well, we wanted to drag it to the end where anything could happen in the last over."
Heinrich Klaasen hit a vital 46 to drag South Africa to 113 after they had been teetering on 23-4, putting up a 79-run partnership with David Miller, who hit 29.
"We're putting Klaasen and Miller under pressure but they've been exceptional," Markram added.
"They've gone back-to-back with crucial partnerships, got us to a score that was luckily enough to win but still one we could defend. It's fantastic for Klaasy to get back in form."
The Proteas won the first of two Tests by seven wickets, easing to a victory target of 106 in their second innings after skittling the hosts for 106 and 307.
It was their first red-ball victory in Asia since 2014, having failed to win in 14 trips to the continent since beating Sri Lanka in Galle a decade ago.
Markram, however, believes there is more to come from their youthful side, hailing the victory as a major breakthrough.
"It's special. We're a pretty young, slightly inexperienced group, so to come to the subcontinent and get a win is great for us and the environment," Markam said.
"This win does a lot for us and gives us a taste of what playing cricket in the subcontinent is like, and it excites us for the challenges that we possibly face here.
"The biggest thing we take from it is the belief and the confidence that we actually can do well here as a team.
"I believe that's where a lot of the game is played, from a confidence and belief and a mental side of things. It will help the team a lot as far as moving forward goes, seeing if we can put back-to-back performances together."
Bangladesh were always playing catch-up after a dismal first innings with the bat, with only a second-innings score of 97 from Mehidy Hasan Miraz forcing South Africa to bat for a second time.
"Everything was in our favour as we won the toss and decided to bat first," Mehidy said. "It is hard to bat on the fourth day on this wicket so we prepared ourselves in that way.
"We couldn't score runs, unfortunately. If we could have scored our second innings runs in the first... First innings runs are very important in Test cricket."
A competitive England score had been chased down in the opener, meaning the world champions were in trouble again when they could only tally 117 on Sunday.
Jos Buttler's tourists slowed alarmingly after reaching the end of the power play on 50-1, crucially losing Phil Salt (25 off 19) in the seventh over before Mehidy Hasan came to the fore for Bangladesh.
Mehidy finished with figures of 4-12, and he then had a key role again with the bat after England had threatened to come back into the match.
Although the Bangladesh reply saw only 32 runs scored in the power play, they still required just over a run a ball at that stage to make 118 – an increasingly achievable target when Mehidy scored 20 off 16, including two sixes.
That contribution would prove decisive – along with a steadier 46 from Najmul Hossain Shanto – as the chase was completed on 120-6 with seven balls remaining, sealing the series ahead of Tuesday's final match.
England stutter after solid start
All out for 117 from the final ball of the innings, England went from a run rate of 8.33 in the power play to 4.79 across the remaining 14 overs.
Even on a difficult pitch, that score – England's eighth-lowest in T20Is – was never likely to be quite enough.
Mehidy makes the difference
Mehidy had career-best figures with the ball, removing Moeen Ali for 15 and then bringing out the tail with the consecutive wickets of Sam Curran, Chris Woakes and Chris Jordan.
But his brisk knock with the bat was every bit as vital, with only Salt, Mehidy and Taskin Ahmed (a late eight off three) scoring at more than a run a ball in the match.
Despite only being able to post 140/9 from their 50 overs at Bay Oval, the Caribbean side was able to use all their experience to bowl Bangladesh out for 136 in reply for their third win of the tournament.
Needing eight runs from the final six balls, with just one wicket in hand, Bangladesh were held in check by West Indies captain Stafanie Taylor who once again came up with a big-time performance as Fariha Trisna fell for a duck on the third ball of the over to hand West Indies a narrow win.
All-rounder Hayley Matthews (4/14), who received player of the match honours, and Afy Fletcher (3/29) that did the majority of the damage with the ball, but the team would have been nowhere without a strong effort at the crease from wicketkeeper Shemaine Campbelle (53*) who propped up a batting innings that had failed to spark.
Bangladesh spinners Salma Khatun (2/23) and Akter (2/23) were the top bowlers for the South Asian team, while skipper Nigar Sultana (25) was the equal top-scorer in a low-scoring innings.
The win sees West Indies jump to third on the standings with three victories from five games, while Bangladesh remain seventh.
For the Caribbean team, Campbelle's half-century was the sole highlight, as Deandra Dottin (17), Matthews (18), and Taylor (4) all fell cheaply. With the team desperate for early wickets to defend the small total it was Matthews that took up the challenge, trapping Shamima Sultana Lbw for a duck in the opening over of the chase.
Fargana Hoque (23) and Sultana looked assured at the crease as they took the score along to 60/2, but Fletcher's three-wicket haul during the middle overs turned the game on its head as the score quickly went to 60/5.
Matthews returned to pick up two more wickets - including the key scalp of Sultana - before Taylor came through with the goods in the final over to seal the result.
At the close of play, having overhauled Bangladesh the West Indies were 340 for 5 and had a lead of 106 runs. The team’s strong position was in large part due to the work of Mayers who put together a dominant 126 from 180 deliveries, providing the base of the West Indies' response to the Bangladesh first innings total of 234.
The batsman came to the crease just before lunch with the team struggling at 132 for four and immediately went to work by putting on a big partnership with Jermaine Blackwood.
The duo steadied a shaky situation with a 116-run fifth-wicket stand after the team had fallen to 137 for 4. Blackwood was dismissed just after tea, by spinner Mehidy Hasan, having added 40 to the tally.
Mayers, who scored 210 on debut against the same opponents last year, pressed on and helped himself to 15 fours and two sixes. Wicketkeeper-batsman Joshua Da Silva joined him at the crease to add 26, and 92 for the sixth wicket, before the close of play.
Earlier, having resumed the day at 67 without loss, West Indies captain Kraigg Brathwaite and John Campbell pushed the score to 100 without loss. The partnership was finally broken when pacer Shoriful Islam produced some extra bounce to Campbell who was then gobbled up by the wicketkeeper, on 45.
Brathwaite was next to follow and was bowled after being deceived by a flighted delivery from Mehidy, shortly after reaching a half-century. The struggles of Raymond Reifer in the number three spot continued. He never looked really comfortable before being dismissed by Khaled Ahmed after getting to 22. Up next, Nkrumah Bonner, who also had success against Bangladesh last year, continued to struggle through a rough patch as he was dismissed for his second duck of the series.
After winning the toss and choosing to bat, the tourists ended day one 220-2 off 68 overs.
McKenzie and Chanderpaul laid a solid foundation with a 130-run opening partnership.
McKenzie led the way with a 124-ball 86 including 12 boundaries and a six while Chanderpaul ended the day 70* off 190 balls including five fours.
Raymon Reifer was the other batsman dismissed for 26 while Alick Athanaze was 35* alongside Chanderpaul at stumps.
