Zimbabwe 118 for 5 (Williams 34*, Ballance 30, Tector 2-17) beat Ireland 114 (Delany 24, Burl 3-29, Masakadza 2-13) by five wickets
Harare: Former England batter Gary Ballance's 30 runs contributed to Zimbabwe's five-wicket win over Ireland in the T20 series opener in Harare.
Sent in to bat, Ireland toiled with Gareth Delany their top scorer on 24 as they only managed 114 in 19.2 overs.
Leg spinner Ryan Burl was the standout performer in a fine Zimbabwe bowling effort with figures of 3-29.
Zimbabwe slipped to 8-2 but Ballance's knock and Sean Williams' unbeaten 34 helped them win in 18.0 overs.
Left-hander Ballance played 23 Tests and 16 one-day internationals for England between 2014 and 2017 but signed a two-year deal with his native Zimbabwe last month having been released early form his county contract with Yorkshire following a racism scandal.
After some recent rain in Harare, the comparatively slow pitch favoured the bowlers, with Ireland's top partnership a paltry 31 for the ninth wicket produced by Delany and Fionn Hand.
Former Ulster Rugby player Ross Adair, joining his brother Mark in an Ireland side minus key trio Paul Stirling, Josh Little and Lorcan Tucker because of their franchise cricket commitments, struck an early four but then departed for five with captain Andrew Balbirnie soon also dismissed as he was caught by Burl off a wide Tendai Chatara delivery to leave the visitors on 12-2.
Harry Tector's struggles with the bat continued as Burl's googly dismissed him for five, with the spinner then repeating the dose to bowl George Dockrell after the Irishman had tried to lift the pace by firing a six.
As the Irish wickets continued to tumble, they looked in serious danger of not reaching three figures as Mark Adair's dismissal by Burl left them on 74-8 after 14.5 overs.
However, Delany's partnership with Hand helped them avoid that indignity and given Zimbabwe's subsequent struggles in their reply, another 20 Ireland runs could have made all the difference.
Bowling in an T20 international for the first time, Tector was denied an immediate wicket with his first ball as Delany spilled a badly-timed attempted drive by Zimbabwe skipper Craig Ervine.
However, Tector got his reward five balls later as Barry McCarthy made no mistake with the catch.
Mark Adair then trapped Tadiwanashe Marumani to leave the hosts on 8-2 but Ballance and Wesley Madhevere steadied the innings by putting on 35 runs for the third wicket.
Balance's departure as he was caught by debutant Ireland wicketkeeper Stephen Doheny off a McCarthy delivery left the hosts on 71-4 in the 13th over.
Despite Burl's dismissal by McCarthy, Williams and Clive Madande, who finished on 18 not out, saw the hosts home.
The sides meet again in Harare in T20 contests on Saturday and Sunday before a three-match one-day series series, which will see Stirling, Little and Tucker returning to the Ireland squad, begins next Wednesday.