England comfortably chase 112 with 30 balls to spare in six-wicket win
Dunkley hits 59 - her maiden T20 international fifty
Hosts take unassailable 10-2 lead in multi-format series with two T20s to play
Brunt takes career best 4-15 as Proteas restricted to 111-9
Seamer moves to 102 T20i wickets, equalling England record
Wolvaardt 55; Ecclestone 2-27, Glenn & Sciver 1-18
Watch highlights on iPlayer from 07:00 BST Friday
Alex Hartley
Former England bowler on BBC Test Match Special
Brilliant, brilliant catch from Sciver in the deep. She runs in, dives forward and grabs the ball just as it is about to hit the ground.
Daniel Norcross
BBC Test Match Special
Brunt has now drawn level with Anya Shrubsole. She is the joint-leading English T20 wicket-taker of all-time and it's a great catch from Sciver.
Wolvaardt c Sciver b Brunt 55 (SA 109-8)
Great grab! Katherine Brunt has four wickets!
Brunt bangs one in shorter and Laura Wolvaardt takes on the pull shot. Nat Sciver has to take a few steps in and settle herself before taking an excellent catch, low to the ground.
Brunt stands there with her arms in the air before a fist pump in the direction of the England dugout.
She's bowled brilliantly and these are now her best ever T20 international figures. Can she get a five-wicket haul? She's got five balls.
Shot!
Laura Wolvaardt finds the gap between mid-wicket and square leg with a strong blow. She's been brilliant.
She keeps the strike with a single out to mid-wicket. Can she get her side up to 125?
Alex Hartley
Former England bowler on BBC Test Match Special
It's not often you see people slog-sweep Sophie Ecclestone and that's because she gets so much bounce on the ball.
She's been slog-swept for six, goes for the quicker ball and then gives it the finger pointing to the dressing room as if to say, 'don't you ever, ever do that again!'
Jafta b Ecclestone 7 (SA 103-7)
Immediate revenge for Sophie Ecclestone.
Sinalo Jafta goes again but misses a quicker, flatter ball from Ecclestone and the ball crashes into off stump.
Ecclestone holds her left arm up in the air and points with a straight face on as if to say "yeah, you don't hit me for six".
Daniel Norcross
BBC Test Match Special
Jafta swings for the hills and has that gone all the way? It has!
Hello!
Sinalo Jafta gets down on one knee and slog sweeps Sophie Ecclestone over mid-wicket for the first six of the night.
Shot.
Here's how England picked up the wickets of Mignon du Preez and Chloe Tryon...
After a good over for South Africa, England fight straight back.
Just two runs and the wicket come off the 18th over.
They are well and truly on top.
Alex Hartley
Former England bowler on BBC Test Match Special
She tried to give herself room, she stepped outside leg stump but got a thick outside edge and it just looped up.
Katherine Brunt has three-for and has put England on top. So much so that she didn't bother celebrating that one.
Daniel Norcross
BBC Test Match Special
Tucker couldn't get enough bat on it and offered up the simplest of catches to Sophia Dunkley at cover.
Tucker c Dunkley b Brunt 8 (SA 96-6)
Simple catch!
Delmi Tucker looks to give herself some room and go over the off-side but chips up a simple catch to Sophia Dunkley.
Brunt has three.
Daniel Norcross
BBC Test Match Special
Wolvaardt has kept this innings together, coming in at number four. Which did raise some eyebrows.
Another half-century for Laura Wolvaardt.
She's so talented.
South Africa have to get her at the top of the order and give her as many balls as possible.
Alex Hartley
Former England bowler on BBC Test Match Special
I feel like Wolvaardt has to face the majority of the balls that are left to get South Africa up to a competitive score.
Daniel Norcross
BBC Test Match Special
It's been predictably a bit lacklustre from South Africa. But you have to give credit to the England bowlers.
Decent over for South Africa as they take Issy Wong's final six balls for 10 runs.
She dropped a little short and Laura Wolvaardt was able to ride the pull shot well and pick up four runs through square leg.
Wong finishes with 0-19 from her four overs.
Daniel Norcross
BBC Test Match Special
South Africa are going nowhere, really.
Alex Hartley
Former England bowler on BBC Test Match Special
Quicker ball from Sophie Ecclestone, that was 60mph. That's nearly as fast as Kate Cross, she bowls 64-65mph.