Ireland hand Pakistan a reality check ahead of T20 World Cup
Put into bat, Pakistan managed a modest 182-6 against the limited bowling resources of their opponents at Castle Avenue.
Skipper Babar Azam made 57 and opener Saim Ayub contributed 45 but it was not really a flying start as Pakistan reached the 100-mark in the 13th over.
Iftikhar Ahmed smashed 37 not out off 15 balls down the order but Pakistan still settled for a middling total.
Andy Balbirnie (77) top-scored for Ireland, who chased down the target with one ball to spare to go 1-0 up in the three-match series.
"The pitch was two-paced. I think 190 would have been a par score," Babar said after Pakistan's loss.
"I don't think we executed the plans. We attacked in the first six overs but didn't finish well.
"I think we were ahead in the first 10 overs but not in the last 10 overs."
Pakistan will play four T20 matches in England later this month before the 2009 champions begin their World Cup campaign with a June 6 match against tournament co-hosts United States in New York.