When West Indies surged to post 321-8, they knew every team making 300-plus batting first had won in this World Cup, eight times out of eight.
But Bangladesh treated the fact like fluff on a shirt, flicking it off as they strolled to 322-3 to win with 51 balls to spare.
Shakib Al Hasan starred in the comeback with 124 not out, his second successive century in the tournament, and Liton Das added 94 not out in his World Cup debut. They combined for an unbeaten 189 in 22.3 overs, receiving plenty of bad deliveries to treat ruthlessly.