Mohammad Hafeez scored his 11th ODI century to guide Pakistan to a six-wicket win over England and give the Asian side a one-nil lead in the four-match series in Abu Dhabi.
The 35 year-old Hafeez scored an unbeaten 102 as Pakistan recovered from 15 for two and then 41 for three to comfortably chase down a target of 217 with more than six overs to spare.
The left-arm seamer Reece Topley, playing in his second ODI, gave England hope when he picked up the wickets of Azhar Ali (8), Bilal Asif (2) and Younis Khan (9), who was playing in his final ODI, before the 10th over.
However, Hafeez first shared in a fourth wicket stand of 70 with Shoaib Malik (26) and then combined with Babar Azam (62*) to put on an unbeaten 106 to see Pakistan to victory.
Topley finished with respectable figures of three for 26 in nine overs while offspinner Moeen Ali took the wicket of Malik but it wasn't enough.
Earlier, England themselves were in deep trouble with the bat as found themselves 14 for three in the fourth over after Jason Roy (0), Joe Root (0) and Alex Hales (10) fell cheaply.
It was a partnership of 133 between captain Eoin Morgan and James Taylor that resurrected a sinking England ship that saved the day.
Morgan went for 76 in the 31st over when he edged spinner Malik to wicketkeeeper Sarfraz Ahmed and the Three Lions' innings fell apart after his dismissal.
Taylor was out for 60, also to Malik, while Chris Woakes contributed 33 but the total of 216 all out was never going to be enough for Pakistan.
Giant paceman Mohammad Irfan took three for 35 in 10 overs while Malik recorded figures of two for 45 in his allotted overs.
The second game of the series takes place at the same venue on Friday.