SA 152-4published at 26.2 overs
Chloe Tryon has had enough of waiting around.
She launches Alice Davidson-Richards over her head for a powerful boundary.
England win by 109 runs
SA 262 all out: Tryon (70), Kapp (62), Wolvaardt (56); Davidson-Richards 3-35, Dean 3-42, Lamb 3-42
Eng 371-7: Beaumont 119 (107), Lamb 65 (66), Knight 63 (49); Khaka 2-64
England lead multi-format series 8-2 before three T20s
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Ffion Wynne and Sam Drury
Chloe Tryon has had enough of waiting around.
She launches Alice Davidson-Richards over her head for a powerful boundary.
Anya Shrubsole
Former England bowler on BBC Test Match Special
It is hard to see how South Africa are chasing these down.
Here's how Emma Lamb took her first ODI wicket.
It's not been Sune Luus' day, has it?
Thanks, Sam! So, a lot of work for South Africa to do still. England won't want to be out there for 50 overs so can they take these last six wickets?
Not with balls like that. Issy Wong pitches one halfway down that sits up nicely for Marizanne Kapp to slap away to the boundary. And that'll be drinks.
We've reached the halfway stage of the innings and South Africa are a fair way short of being halfway to their target.
Kapp is starting to motor, though, and to see if she can get her side anywhere close to their mammoth target, I'll hand you over to Ffion Wynne.
Target 372
In the slot from ADR and Kapp climbs into it, launching the ball over long-on for six. That sounded good off the bat, the result was never in doubt.
Anya Shrubsole
Former England bowler on BBC Test Match Special
In time, 80mph will become the norm for women's cricket. Issy Wong is one who could get there for England, but the young Aussies Darcie Brown and Tayla Vlaeminck have also got close.
Issy Wong is hunting for wickets, going very full but on this pitch, with this outfield, there is very little margin for error and when she doesn't get it quite right, Kapp thumps convincingly through mid-off for four.
A single cut out to the sweeping fielder ends the over.
Anya Shrubsole
Former England bowler on BBC Test Match Special
Yeah, she won't be doing that all the time. She's new, she'll soon learn!
Jonathan Agnew
BBC cricket correspondent on Test Match Special
Issy Wong has gone for the Stuart Broad bandana.
She's got some good pace. She bowled a lot in the warm up, too!
Issy Wong has completed her warm-up and is coming on to bowl.
Jonathan Agnew
BBC cricket correspondent on Test Match Special
The target is far, far away but it's good to see South Africa playing with some spirit.
Target 372
Here comes Kapp! The short ball from Davidson-Richards is pulled powerfully behind square and when the seamer goes fuller, Kapp is waiting to pump it back over wide long-on for a one-bounce four.
Two top class shots.
Jonathan Agnew
BBC cricket correspondent on Test Match Special
She heard you, Anya. She's warming up.
Anya Shrubsole
Former England bowler on BBC Test Match Special
I'd like to see Issy Wong back on. She got Chloe Tryon out with a nice bouncer at Bristol so that would be a good aggressive option.
Tryon 3, Kapp 4
There is no great attacking intent just yet from Kapp or Tryon as Lamb continues.
Kapp gets two with a delicate late cut that Beaumont does well to haul in.
The calm before the storm?
Well, it could be an entertaining few overs with Kapp joined by Chloe Tryon. Neither of them are known to hold back, they will swing the willow - and they need to!
Alex Hartley
Former England bowler on BBC Test Match Special
What a good catch! Lauren Bell has got a long way down to go but she takes it at her ankles.
Goodall c Bell b Davidson-Richards 24 (SA 109-4)
A wicket second ball for Alice Davidson-Richards and South Africa are crumbling! It's a superb catch from Lauren Bell!
Goodall was trying to get things moving again for her side but in doing so, ends up chipping the ball towards mid-on and Bell dives forward to make an excellent grab.
Alex Hartley
Former England bowler on BBC Test Match Special
She's had a stinker.