Afghanistan bowled Ireland out for 211 to record a 39-run one-day international victory at the Civil Service Cricket Club, Stormont and take a 1-0 series lead.
The tourists were put in to bat, with Mohammad Shahzad and Javed Ahmadi (29) making 76 for the opening wicket.
Shahzad helped push the score into three figures before he was out for 66 in the 23rd over, one of four wickets to Kevin O'Brien.
Afghanistan reached 124 for two but lost Rahmat Shah (14) and Asghar Stanikzai (0) in consecutive overs.
A 70-run fifth-wicket stand between Najibullah Zadran (59) and Samiullah Shenwari (24) then steadied the ship.
Ireland finished off the tail in 49.2 overs, Afghanistan all out for 250 as Barry McCarthy also claimed four wickets.
Although Ireland started their reply well, with William Porterfield (25) and Ed Joyce (62) putting on 71 for the opening wicket, there was not enough support from the middle order.
Stuart Poynter was out for a three-ball duck and while O'Brien scored 35, Ireland - comfortably beaten by Sri Lanka last month - saw the final five wickets fall for just 22 runs.
Rashid Khan was the pick of the Afghanistan bowlers with three for 28, while Gulbadin Naib returned figures of three for 45.
Sunday's opening match in the five-game series hosted at Stormont had been rained off, with the third match set for Thursday.