Centuries from Tamim Iqbal and Mushfiqur Rahim powered Bangladesh to their highest total and a victory against Pakistan in ODI after a gap of 16 years.
The 79-run win in Dhaka gave Bangladesh a 1-0 lead in the three-match series and their second victory in the 50-over format against Pakistan. They also defeated them in Northampton during the 1999 World Cup in England.
Tamim (132) and Mushfiqur (106) added 178 in 130 balls for the third wicket as Bangladesh recovered from a sluggish start to post their highest ODI total of 329-6 after winning the toss and opting to bat against a new look Pakistan side.
In reply, the visitors were bowled out for 250 in the 46th over, despite half-centuries from Azhar Ali (72), debutant Mohammad Rizwan (67) and Haris Sohail (51).
Azhar, who replaced the retired Misbah-ul-Haq as Pakistan's new ODI captain, would have been delighted with the performance of his bowlers in the first 20 overs as Bangladesh limped to 67 for two.
But Tamim, who scored his first ODI hundred since March 2013, and former captain Mushfiqur, whose 77-ball knock contained 13 fours and two sixes, turned the momentum in Bangladesh's favour with their record stand - the highest for any wicket for the side in the 50-over format.
With some of their first-choice bowlers ruled out with injuries before the start of the series, Pakistan had high hopes of off-spinner Saeed Ajmal, who has returned to international cricket after remodelling his illegal bowling action.
Ajmal bowled well for his first five overs, giving away only 11 runs, but ended with figures of 0-74 from his 10, his worst figures in ODIs.
Left-arm paceman Wahab Riaz, who was impressive during the recent 50-over World Cup in Australia and New Zealand, was once again the pick of the Pakistan bowlers with figures of 4-59.
But Pakistan's poor fielding and dropped catches cost them again as the tourists were unable to get close to the target in the end.
Bangladesh 329-6 in 50 overs (Iqbal 132, Riaz 4-59)
Pakistan 250 all out in 45.2 overs (Azhar 72, Taskin 3-42)
Source: Al Jazeera and agencies