England 147 for 7 (Taylor 74*) beat South Africa 132 for 6 (van Niekerk 52, Shrubsole 3-25) by 15 runs
England's bowlers fought back to secure a 15-run win in the first T20 with South Africa, after Sarah Taylor's blistering, unbeaten 74 had masked a top-order failure with the bat.
Chasing 148 to win, South Africa openers Dane van Niekerk and Trisha Chetty put on a 96-run stand but Anya Shrubsole claimed three wickets to put the brakes on and put England 1-0 up in the three-match series.
Van Niekerk struck a half-century, to go with 2 for 26 with the ball, but she fell to the returning Shrubsole and South Africa were left needing 51 from the last five overs. Jenny Gunn had Chetty lbw in the next over and South Africa's middle order could not achieve the required acceleration.
Marizanne Kapp was next to go, a wicket for Danielle Hazell, and Shrubsole then effectively sealed the win in the penultimate over, removing the dangerous Lizelle Lee - via a brilliant Amy Jones catch at deep midwicket - and captain Mignon du Preez. Gunn bowled the final over, with 24 required, and conceded just eight while having Chloe Tryon stumped.
South Africa had initially been on top with the ball as well, reducing England to 41 for 3 and 81 for 5. Taylor, coming in at No. 3, initially found an ally in Heather Knight to put on 38 in three-and-a-half overs, and then Georgia Elwiss, playing her first T20 international innings, who also made 18.
Taylor, the No. 3-ranked T20 batsman in the world, struck 11 boundaries and showed her confidence with a couple of trademark scoops. Shrubsole also played a part with the bat, as she and Taylor took 18 off Shabnim Ismail's final over to push England out of sight.
The second and third matches in the series will be played as double-headers with the men's T20s in Cape Town, on Friday, and Johannesburg, on Sunday.