Lefthander Zazai's score was the second-highest individual innings in T20 internationals. Australian Aaron Finch holds the record with 172 against Zimbabwe in Harare last year. Ireland captain Paul Stirling made a fighting 91 off 50 balls in his team's reply of 194-6 but Ireland fell well short of the target to trail 2-0 in the three-match series.
Stirling and Kevin O'Brien (37) shared a 126-run opening wicket stand but both fell in successive overs before prolific leg-spinner Rashid Khan ran through the batting by claiming 4-25. In a record-breaking day for Afghanistan, openers Zazai and Usman Ghani (73) shared a record 236-run partnership — for any T20 wicket — off 105 balls.
Ireland got a chance to dismiss Zazai on 72 in the 10th over, but George Dockrell missed a sitter at point boundary. Stirling used eight bowlers, including his one over of off-spin which went for 24 runs.
Zazai reached his half-century off 25 balls and then completed his hundred off 42 balls by smashing Stirling for a six over long on. Zazai's 16 sixes in an innings were two more than Finch's previous record of 14 against England at Southampton in 2013.
Afghanistan will look for a series sweep when both teams meet again on Sunday.
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