England were beaten by 14 runs on the Duckworth-Lewis-Stern method as South Africa won a rain-interrupted opening T20 clash in Cardiff.
Rain in the Welsh capital had reduced the contest to nine overs per side with the start delayed until 8.50pm.
South Africa had reached 97 for five from 7.5 overs – hitting nine sixes in total – before a short shower ended their effort and left England with a tough revised target.
England were tasked with scoring 69 from 30 balls, and it proved beyond them as Marco Jansen and Corbin Bosch were curiously allowed to bowl two overs each.
Kagiso Rabada was back in the Proteas attack after missing the ODI series and removed Phil Salt with his first ball.
The England opener was crestfallen after sending the ball skywards and straight to Kwena Maphaka just inside the backward square leg boundary rope.
Jacob Bethell smashed one six after his Southampton ODI heroics on Sunday, but miscued Jansen to give Donovan Ferreira a catch running back from cover.
Harry Brook went for a three-ball duck after sending a leading edge high into the night air and wicketkeeper Ryan Rickelton did not have to move to complete the dismissal.
England’s hopes were effectively ended when Buttler, having hit three sixes and one four in his 25, snicked Jansen behind from the final ball of the penultimate over.
Tom Banton departed next ball and, despite some final-over resistance from Sam Curran, the England reply finished on 54 for five.
England had named their XI on Tuesday but made a late change because of the conditions.
Jofra Archer was omitted after his four-wicket burst in the record ODI victory against South Africa on Sunday and Luke Wood was brought in.
Brook chose to chase after winning the toss and Wood struck with his second delivery as Rickelton nicked behind to Buttler for a golden duck.
Wood struck again as Brook snaffled an excellent diving catch to remove Lhuan-dre Pretorius and leave South Africa 33 for two.
Aiden Markram was given two lives as Brook could not get near a swirling ball over his shoulder and Salt put down a more straightforward chance in the deep.
It was third time unlucky for the Proteas skipper off Adil Rashid as Wood accepted a steepler to end a 14-ball innings worth 28.
Dewald Brevis provided momentum with successive sixes off Liam Dawson to the short straight boundary, and muscled a third way over the mid-wicket boundary.
Brevis was threatening to take the game away from England until Curran made a dream return to England colours.
Curran had been absent since November 2024 and had not featured under head coach Brendon McCullum. But the all-rounder made an instant impact as Brevis, 23 off 10 balls, found Dawson at backward point.
Tristan Stubbs made a quickfire 13 before Jamie Overton bowled him, punishing an audacious reverse scoop.
Ferreira had hit three sixes in an 11-ball 25 before rain curtailed their innings.
The three-match series continues at Old Trafford on Friday with the finale at Trent Bridge on Sunday.