Eng 215-5published at 32 overs
Amy Jones comes in and plays the last couple of balls of the over into the covers.
Four to win.
England 219-5: Lamb 102, Sciver 55; De Klerk 2-44
Lamb hits maiden international ton off 91 balls; Sciver hits 55 after taking 4-59
SA 218 all out - Tryon hits 88
Multi-format currently level at 2-2 after drawn Test
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Sam Drury
Amy Jones comes in and plays the last couple of balls of the over into the covers.
Four to win.
Alex Hartley
Former England bowler on BBC Test Match Special
I tell you what, the umpires have had a shocker today, haven't they?
Knight lbw b Khaka 20 (Eng 215-5)
It's more than close, it's out! Three reds and Knight is on her way, the ball was clattering into leg stump.
Still four runs to win.
Knight looks to sweep Khaka, misses and there is a half-hearted appeal. However, it looks quite close and they're going to review.
Alex Hartley
Former England bowler on BBC Test Match Special
I'm coming on for the party!
England's innings has been brilliant. It has been so good to watch.
There was a brief moment when it looked as though England might try to nudge and nurdle there way over the line but Danni Wyatt soon decided against that.
The England number six whips the ball through mid-wicket, four runs and they need just 10 to win now.
Anya Shrubsole
Former England bowler on BBC Test Match Special
That was a brilliant innings.
She was given her chance and she's laid down a marker.
I don't think we'll get that smile off her face for a while. She hasn't made it back to the changing room yet - she's getting hugged by every member of the team and backroom staff and there are quite a few of them.
Daniel Norcross
BBC Test Match Special
She was looking to finish it in style.
She deserves the pat on the back from Heather Knight because it was a knock for the ages.
Lamb c Khaka b Sekhukhune 102 (Eng 202-4)
The end of a fabulous innings. Short from Sekhukhune, Lamb tried to pull it high over deep backward square but didn't get all of it.
Khaka takes the catch and Lamb walks off to a thoroughly deserved standing ovation. A maiden England century - what a way to take your chance at the top of the order.
Henry Moeran
BBC Test Match Special
She's got more of that than I've ever got of any shot!
Anya Shrubsole
Former England bowler on BBC Test Match Special
That is a great shot by Heather Knight.
She's looking at her bat as if she hasn't got all of that either...
Brilliant from Heather Knight. A little shuffle down the track and then a superb shot back over de Klerk's head, dead straight and all the way for six.
The first maximum of the England innings and it was six from the moment it left the bat.
Anya Shrubsole
Former England bowler on BBC Test Match Special
Lisa Keightley's notebook still baffles me to this day.
It is a normal pad but whatever she writes on the notepad automatically transfers to her iPad.
It must be something in her pen.
I still don't get it.
Target 219
England are just easing their way to victory now. They need just 25 runs more for victory and a mere 21 overs in which to get them.
#bbccricket
Dom: Yes Lamby.
Target 219
There was plenty of emotion in Emma Lamb's celebration, it has not been a straightforward journey for her to get to this stage but I'm sure she'll consider it all to be worth it now.
Arguably, the ignominy of once having to play in the same team as me a few years ago was the low point for her.
Anya Shrubsole
Former England bowler on BBC Test Match Special
That is an unbelievable knock from Emma Lamb. She looks quite emotional to be honest with you. She has batted brilliantly.
The start of her international career has been quite stop-start but she has laid down a market. That is her at the top of the order for the entire international summer now you would imagine.
Henry Moeran
BBC Test Match Special
Just listen to the noise around the ground!
She gets an enormous hug from captain Heather Knight and a massive round of applause from Lisa Keightley.
What a moment for the England opener! A maiden international hundred!
She gets there in style as well, carving the ball away past backward point - a 15th boundary of the innings and she reaches three figures from just 91 balls.
Superb innings and, at 24, she'll hope it's the first of many.
Phil Long
BBC Test Match Special statistician
The partnership between Nat Sciver and Emma Lamb was worth 89 off exactly 11 overs.