England began their ICC Champions Trophy with an eight-wicket thrashing of Bangladesh, inspired by Joe Root's century, but victory came at a cost for the hosts.
A strength in batting was laid bare as Alex Hales (95) and Root (133 not out) anchored a chase of 306 at The Oval that rarely required England to move out of second gear, although Jason Roy's (1) latest single-figure score will pose a selection headache moving forward.
Eoin Morgan's fine form continued with an unbeaten 75, but the captain has further concerns after Chris Woakes suffered a side strain that could end his competition early. Root also rolled an ankle at the crease, but it did not stop him reaching a 10th one-day international hundred.
Tamim Iqbal batted beautifully for a fine 128, while former skipper Mushfiqur Rahim hit 79 off 72 balls. As a score in the mid-300s looked possible, the pair fell in consecutive deliveries and Sabbir Rahman's 15-ball 24 dragged them to 305-6.
Picking a strong batting line-up - in response to falling 84 all out in their final warm-up against India - worked against Bangladesh, however, as their bowling lacked the creativity and guile to unsettle a powerful England side that cantered to victory.
Though ultimately left unfulfilled, passionate pockets of Bangladesh fans in London erupted through much of Tamim's innings, though he took 11 balls to get off the mark in a circumspect start.
Soumya Sarkar was dropped by Moeen Ali, but the opener only made 28 before Ben Stokes' first contribution was to account for him and Imrul Kayes contributed just 19.
Imrul's departure brought Mushfiqur and Tamim together, however, and the pair's stylish counter-attack may have had Bangladesh dreaming of stunning England again after their Test success last year and the left-hander's ninth ODI hundred deserved to have more of a say.
Though momentum was sapped at the end of their innings, the Tigers were lifted again when Roy fished at a Mashrafe Mortaza delivery well outside off and Mustafizur Rahman took a good catch at backward square. Roy's last five scores now read: 0, 20, 1, 8, 4, 1.
But Hales and Root were serene as they piled on 159 runs together, Root's nasty stumble on the pull shot their only scare until Hales went after Sabbir Rahman and picked out replacement fielder Sunzamul Islam with a skewed sweep shot.
Morgan had a life when Tamim was deemed to have grounded a diving catch by the third umpire and used it to good effect, bringing up a 33rd ODI fifty, but the crowd was lifted to its feet when Root reached three figures, despite struggling on his right leg.
A calm chase was capped by Root smashing his way to his highest ODI score as England became the first side to chase over 300 in Champions Trophy history - though this owes more to the changing face of white-ball cricket since 2013.