Jordan Cox's first international fifty propelled England to a series-sealing, six-wicket win over Ireland in the final T20l at Malahide - after Sonny Baker suffered another chastening debut.
Jacob Bethell's side reached their target of 155 with 17 balls to spare to secure a 2-0 triumph having won the opening game by four wickets before the second fixture was entirely wiped out by rain.
Jos Buttler (0) and Bethell (15) fell early - Buttler to a superb one-handed catch from Curtis Campher in the covers - but Cox (55 from 35 balls) impressed in his first England knock in a year, cracking four sixes and the same number of fours as he cantered past his previous top score of 17 across five white-ball innings for his country.
Earlier on, Hampshire quick Baker shipped 52 runs from a wicketless four overs - conceding six fours and three sixes - having been spanked for 0-76 from seven overs on his one-day international bow against South Africa at Headingley earlier this month.
Ireland posted 154-8 after being inserted with Ross Adair (33 off 23) pummelling Baker in the powerplay and Gareth Delany (48no off 29) doing likewise at the death, the latter hitting back-to-back sixes, after the hosts slipped from 52-1 to 102-7.
Adil Rashid (3-29), Liam Dawson (2-9) and Jamie Overton (2-17) impressed for England with the ball and it was a surprise that Dawson only bowled two overs, not his full quota of four.
Cox - who had hobbled off the field after jarring his knee taking a catch late in the Ireland innings - successfully overturned an lbw dismissal on 24 in the chase and shared important stands of 57 and 49 with Phil Salt (29 off 23) and Tom Banton (37no off 26) respectively.
Banton clipped away the winning run before Bethell - deputising as captain for the rested Harry Brook in this series - held the trophy aloft and toasted a good week's work.
England are back in white-ball action in New Zealand from October 18 to November 1 with three T20s and as many ODIs, before attention turns to The Ashes series in Australia, which starts at Perth's Optus Stadium on November 21.
Baker has been tipped as a potential Ashes squad member - he impressed hugely in The Hundred while ruffling the likes of David Warner, Steve Smith, Kane Williamson and Joe Root - but his two white-ball outings for England so far have been disappointing.
The seamer delivered too many half volleys or hittable short balls as Adair and Delany took him apart but Ireland were left to rue some injudicious shots in the middle overs as they lost a clatter of wickets.
Campher (2) skied tamely to long-on, while Harry Tector (28 off 27) was caught reverse-sweeping Dawson during a slump of 6-50, although Canada-born debutant Ben Calitz did fire fleetingly with 22 from 18 balls, including thumping Rashid for six.
Rain delayed the start of England's reply and when it finally began at 4.10pm, it was soon lit up by Campher's stunning catch and then Cox's shots, with one of the batter's sixes hit out of the ground.
Cox - who was bowled by Ireland leg-spinner Ben White with 16 required - has endured rotten luck with injury over the last couple of years, including being denied an England Test debut in New Zealand last winter after fracturing his thumb in the nets.
But he earned his white-ball recall after a player-of-the-tournament display in The Hundred for champions Oval Invincibles, scoring a leading 367 runs with three half-centuries, and this latest classy innings may tempt England to give him further opportunities.
England captain Jacob Bethell at the presentation:
"I couldn't have dreamt it any better really. The rained-out game was a bit unfortunate but to come out on top in my first series as captain is a great feeling.
"We were nice and aggressive all week. We just wanted to carry on that momentum going forward from South Africa and I think we have done that pretty well.
"I am looking forward to letting [Harry Brook] take back the reins as captain when we head to New Zealand."
Ireland captain Paul Stirling at the presentation:
"We take a lot of positives from this series. It was just a shame we couldn't get all three games in.
"We were 15 [runs] short no matter what today, but I'm proud of the way the lads have performed.
"We have plenty of cricket coming up in the lead-up to the [2026] World Cup."
