Shai Hope helped West Indies' bid to climb to fifth place in the World Cup standings as Chris Gayle suffered a miserable Taunton return against Bangladesh.
Hope's 96 from 121 balls was the mainstay of the West Indies' 321 for eight after Bangladesh had won the toss and chosen to bowl in overcast conditions.
The stylish 25-year-old showed patience against a disciplined Bangladesh attack, striking only three boundaries in the first 88 deliveries he faced before opening up with a flat batted six and pulled four off Mustafizur Rahman.
Hope's diligence allowed late-innings impetus from Shimron Hetmyer – who matched the 25-ball 50 of Australia's Alex Carey as the fastest in the tournament – and skipper Jason Holder, who struck 33 from 15 balls.
All that was in stark contrast to the performance of opener Gayle, who looked hopelessly out of touch during his brief 13-ball stay.
Gayle had a successful spell at Somerset a few years ago but he poked around unconvincingly before edging Mohammad Saifuddin for Mushfiqur Rahim to take a smart low catch behind the stumps.
It was the second duck of Gayle's World Cup career, both against Bangladesh, and the prelude to the lowest scoring powerplay of the tournament – 32 for one.
Evin Lewis and Hope patiently rebuilt the innings by putting on 116 in 21.1 overs, the first 100-plus West Indies partnership at this World Cup.
Bangladesh were able to restrict them with some fine fielding, particularly on the boundary rope, and through the crafty spin of Shakib Al-Hasan and Mehedi Hasan.
Lewis eventually started to unwind before falling for 70 off 67 balls, sending Shakib straight to substitute fielder Shabbir Rahaman on the long-off boundary.
Nicholas Pooran, with 25 from 30 balls, and Hetmyer continued to attack the short boundaries as the Bangladesh bowlers came under concerted pressure for the first time.
Hetmyer, who reached 1,000 career ODI runs on making 34, smashed four fours and three sixes.
As well as equalling Carey's record at this tournament, it was the third fastest by a West Indies batsman in World Cup history.
But Hetmyer's innings came to an end when he skied Mustafizur to Tamim Iqbal at mid-wicket.
Holder maintained the momentum by smashing four fours and two sixes before Hope, attempting a big finish, fell four short of his century by becoming Mustafizur's third victim.
Saifuddin also claimed a third wicket by bowling Darren Bravo with the final ball of the innings, but the West Indies had managed to post a score set to test Bangladesh.