|Second Royal London Twenty20 international, Worcester|
|South Africa 148-6: Bosch 61; Glenn 2-27|
|England 151-4: Sciver 47; Khaka 1-10|
|England won by six wickets; England lead multi-format series 12-2|
England overcame an improved performance from South Africa to comfortably win the second Twenty20 by six wickets at Worcester.
The hosts chased 149 with an over to spare, Nat Sciver hitting a composed 41-ball 47 and Danni Wyatt a more aggressive 39 from 24 balls.
Having made 111 in Thursday's first T20 defeat, South Africa posted 148-6.
Anneke Bosch top-scored with 61 in a century stand with fellow opener Lara Goodall, who made 42.
But the visitors slumped from 102-0 after teenager Alice Capsey took Goodall's wicket in her first over in international cricket.
Katherine Brunt then became England's leading wicket-taker in international T20s when she bowled Laura Wolvaardt in the final over for 21.
While it was a significant improvement on the batting performance at Chelmsford, England were still comfortable in pursuit.
Sophia Dunkley continued her aggression at the top of the order with 23 from 15 balls while Amy Jones ended 20 not out.
Sciver was standing in as captain for the injured Heather Knight, who missed out with a hip injury less than a week before the start of the Commonwealth Games.
Victory meant England extended their lead to 12-2 in the multi-format series. The final T20 takes place at Derby on Monday at 18:30 BST and is live on BBC Two.
Improvement, but not enough for South Africa
South Africa's batting has failed to fire throughout the white-ball leg of the series, the void left by power-hitter Lizelle Lee's retirement seeming to grow with each game.
It remains a problem at the top of the order, as despite Bosch and Goodall's improvement, they still only managed to reach 34-0 at the end of the opening powerplay.
But they showed fight and grit - something that had previously been missing.
Despite the slow start, they grew in confidence and accelerated, setting a platform for the likes of Sune Luus, Chloe Tryon and Mignon du Preez.
But two generations intertwined as Brunt and 17-year-old Capsey - who was just 10 days old when the former made her international debut - took their milestone wickets.
Brunt's wicket was her 103rd in the format for England, taking her clear of her former team-mate Anya Shrubsole who retired earlier this year.
Leg-spinner Sarah Glenn also took two wickets to stall South Africa's momentum and they failed to reach the 160 mark that they would have been aiming for.
The gulf between the sides remains stark, as Dunkley and Wyatt had the confidence to attack from the offset, the former continuing her incredible form by smashing 18 from the third over before being caught at long-on going for one six too many.
Wyatt looked set to lead England home before she was dismissed by a fantastic diving catch from opposing skipper Luus in the outfield.
But England were 51-2 after the powerplay, the back of the chase already broken, which allowed Sciver to play an array of creative shots before she was unfortunately run out backing up at the non-striker's end with just nine more runs needed.
Maia Bouchier settled any nerves by hitting two fours in her five balls to seal the win - England's fifth in five white-ball matches in this series.
'We just want to keep being relentless' - reaction
England captain Nat Sciver: "Different challenges were thrown at us, particularly when we were bowling.
"They came out with great intent and really put us under pressure - we did really good job of dragging it back in the final 10 overs of their innings.
"To come out with that intent with the bat, when conditions were trickier than the other day, I thought was really good.
"We just want to keep being relentless with our attacking mindset."
South Africa captain Sune Luus: "We spoke about giving us a platform for Chloe [Tryon], myself and Laura [Wolvaardt] to come in and tee off at the end.
"Unfortunately myself and Chloe didn't come off which could have given us an extra 20-30 runs. They did well and I think that is the confidence they needed to kick on for the next game."
Injured England bowler Tash Farrant on BBC Test Match Special: "England look in a really strong place at the moment.
"They have been ruthless with their performances and just haven't let South Africa in at all. They are building up nicely for the Commonwealth Games."