Having won the toss and elected to field, Bangladesh captain Shakib Al Hasan put his side in the driving seat by claiming three key wickets, while Mehidy (3-25) mopped up the tail. Rahmanullah Gurbaz top-scored for Afghanistan with 47.
Mehidy then played a significant part in Bangladesh’s reply with 57 off 73 balls as the 2015 quarter-finalists chased down their target of 157 in 34.4 overs.
Afghanistan, relatively well-placed at 47-1 and 112-2 lost their last eight wickets for 44 runs.
Shakib, who in the corresponding World Cup fixture four years ago took 5-29 in Bangladesh’s 62-run win, made the initial breakthrough Saturday when he had Ibrahim Zadran caught on the sweep.
Several Afghanistan batsmen gave their wickets away, with only opener Rahmanullah Gurbaz (47) offering much resistance.
As It Happened
But Gurbaz, who made 145 in a one-day international against Bangladesh in July, fell when, seemingly frustrated at the lack of support from the other end, he holed out off paceman Mustafizur Rahman to Tanzid Hasan in the covers.
Afghanistan’s plight was summed up when tailender Mujeeb Ur Rahman walked out to bat without wearing a box or athletic protector.
Bangladesh stumbled early on in their chase.
Tanzid Hasan was run out by Najibullah Zadran and the Tigers were 27-2 when Liton Das played on to paceman Fazalhaq Farooqi.
But Afghanistan, who needed to take every chance when defending such a low total, then saw Najibullah drop Mehidy on 12, when he floored a regulation catch at backward point.
Mehidy was missed again on 23 when he uppercut Naveen-ul-Haq only for Mujeeb to drop a one-handed catch at deep third man when he could have could have gone for the ball with both hands.
Mehidy punished those lapses with a 58-ball fifty including four fours.
He then survived a close lbw appeal from Mujeeb following a prolonged review before he was brilliantly caught one-handed by a leaping Rahmat Shah at mid-off to end a third-wicket partnership of 97.
But by then Bangladesh were in sight of victory.
Najmul, having already hit Mujeeb for six, went on to an 80-ball fifty.
He finished the match with successive fours, the second coming from a fumble at mid-off, as he continued an impressive 2023 where he is averaging nearly 55 in ODI cricket.
(With inputs from AFP)