Ireland skipper Paul Stirling won the toss and elected to bat first in what was the first T20 clash of three between the two sides. Stirling was the only top-order Ireland batsman to get going with the right-hander getting to 23 before his stay was ended by Nabi.
Mujeeb ur Rahman struck early for Afghanistan by dismissing Kevin O’Brien as Nabi held on to a straightforward chance at long-on before Andy Balbirnie fell to Karim Janat.
Once Stirling was sent back, Afghanistan tightened the screws with Rashid Khan and Nabi getting the better of Stuart Thompson and Simi Singh respectively.
After being reduced to 65-6, Ireland fought back through an unbeaten 67-run stand between George Dockrell (34) and wicketkeeper Stuart Poynter (31) to post a respectable 132-6 in their 20 overs.
In reply, Afghanistan started poorly in the chase with Boyd Rankin striking twice with the new ball. The Ireland pacer accounted for Hazratullah Zazai and Karim Janat as the Afghans lost three quick wickets inside four overs.
Once Samiullah Shinwari was dismissed off the last ball of the powerplay by Josh Little, Afghanistan were truly struggling and things went from bad to worse when Sharafuddin Ashraf was caught by Little at third-man.
At 50-5, Nabi and Najibullah Zadran took control of the chase for Afghanistan with the pair adding 86 runs between them in just over 11 overs to seal a win. Nabi finished off the chase with a boundary off the second delivery of the final over and remained unbeaten on 49 (40).
Zadran, meanwhile, scored a handy 40 (36) as Afghanistan took a 1-0 lead in the three-match series. The second T20 between the two sides will be held at the same venue on Saturday.
Ireland: 132-6 (20 overs)
George Dockrell: 34 (28)
Mohammad Nabi: 2-16 (four overs)
Rashid Khan: 2-21 (four overs)
Afghanistan: 136-5 (19.2 overs)
Mohammad Nabi: 49 not out (40)
Najibullah Zardan: 40 (36)
Boyd Rankin: 2-38 (four overs)
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