James Taylor starred for England with his sixth One-Day International half-century, but it was Pakistan that emerged victorious in Abu Dhabi.
An inspired bowling performance from the men in green, guided by the pace duo of Mohammad Irfan and Anwar Ali, followed by an unbeaten century from Mohammad Hafeez, sent the hosts to victory with 38 deliveries to spare.
After the tourists had chosen to bat first, an early collapse left them 14-3 before Taylor and Eoin Morgan combined to rescue them from the poor start.
However, a further collapse saw England bowled out for 216 before Hafeez eased his side to the required total to go 1-0 in the four-match series.
Looking to comeback from the 2-0 Test series loss, a new look top order was soon in trouble as the Pakistan seamers made early inroads.
Jason Roy was bowled second ball by the seven foot one left-armer, Irfan, before his new ball partner, Ali, trapped Joe Root LBW despite reviewing the decision.
Alex Hales scored ten from seven deliveries but - when he was caught at first slip Younus Khan, who was making his final appearance prior to retirement from ODI cricket - England found themselves three down and in trouble.
Morgan and Taylor set about rebuilding the innings, adding 133 in the next 27 overs, only for the wicket of the captain to induce a second damaging clutter of wickets.
Morgan had made 76, his fourth score of 50 or more in his last five ODIs, before edging behind off Shoaib Malik, starting a run of four wickets for 14 runs.
Jos Buttler was run out for one attempting a quick single with Taylor, before the Nottinghamshire right-hander fell to a diving catch from Azhar Ali having made 60, continuing his fine run of form in recent ODIs for England.
Pakistan’s fielding continued to back up the work of the bowlers and Babar Azam pulled off an outstanding one-handed effort at midwicket to account for Moeen Ali (7).
A battling 33 from Chris Woakes, who was run out in the final over, and 13 from David Willey, elevated the England score to 216 all out, but it proved to be well under par.
Early wickets gave them hope as Reece Topley, on debut, recovered from some early nervous wides to rip through the Pakistan top order, trapping Ali and Bilal Asif LBW in quick succession.
Topley followed that with the prized wicket of Younus Khan, caught at mid-on for nine, ending the white ball career of the Pakistan legend who left the field to generous applause from the entire England team.
However, that was the last of the joy for England for some time as Mohammad Hafeez and Malik steered Pakistan away from 41-3.
England’s spinners failed to apply the same pressure as their counterparts and the tourists soon found themselves on the back foot defending a low total.
Hafeez was in brilliant form, carrying his run of scores through from the Test series whilst Malik, recently retired from the longest format, was playing an effective supporting role.
However, just as England were getting desperate for a breakthrough, Malik gifted his wicket to the tourists, flicking Ali into the hands of Roy at midwicket.
Azam, in just his fourth ODI, joined Hafeez and immediately looked to up the tempo, smashing his first international six off Adil Rashid.
The powerful Azam (62*) hit his third six to go to a quick-fire fifty before Hafeez went to his first ODI hundred against England, his 11th overall, off 127 balls as Pakistan cantered to a six-wicket victory.
England are returning to the scene of their Ashes triumph in 2016 for Royal London One-Day Internationals against Sri Lanka and Pakistan.
Don't miss the opportunity to watch some of the best players in the world go toe-to-toe in the unique surroundings of Trent Bridge and secure your seats now.