England's Jonny Bairstow bludgeoned a brilliant unbeaten 86 from 48 balls as the tourists chased down 180 to beat South Africa by five wickets with four balls to spare on a slow wicket in the first Twenty20 International at Newlands on Friday.
Sent into bat, South Africa posted a respectable 179 for six in their 20 overs, before claiming early wickets to have England in trouble in their reply.
But Bairstow, batting in an unfamiliar number four position, led the fightback as he sat deep in his crease and smashed nine fours and four sixes with the kind of exquisite timing few other batsmen found on the day.
The win will be pleasing for captain Eoin Morgan, who said this week he did not know his best XI in the shortest format but could already have had some questions answered ahead of the second fixture in the three-match series in Paarl on Sunday.
South Africa's innings was anchored by the experienced Faf du Plessis (58 from 40 balls), who was especially brutal on Tom Curran (1-55), smashing the England seamer for 24 runs in his second over that contributed to the bowler's most expensive figures in international Twenty20 cricket.
Brother Sam Curran (3-28) exacted some family revenge when he had Du Plessis caught on the boundary by Chris Jordan and was the pick of the visitors' attack with his career-best figures and clever change of pace and ability to surprise with the short ball on a slow wicket.
Quinton de Kock (30 from 23 balls) and Rassie van der Dussen (37 from 28 balls) also provided useful runs for the home side.
England were in early trouble in their reply, losing Jason Roy (0) second ball to George Linde as South Africa took pace off the ball at the start of the innings.
When Jos Buttler (7) and Dawid Malan (19) fell the visitors had slumped to 34-3 in the sixth over. But Bairstow and Ben Stokes (37 from 27 balls) rallied, putting on 85 in 8.4 overs for the fourth wicket to drag England back into the contest.
England still needed 51 from the final four overs, but when Beuran Hendricks conceded 28 runs in his last over, the game swung heavily in their favour.