Sciver & Davidson-Richards hit centuries as England recover brilliantly to close on 328-6, leading by 44
Sciver ends on 119*, Test debutant Davidson-Richards caught for 107 off final ball of day
Hosts were 121-5 after lunch in reply to South Africa's 284
Jones bowled by spinner Mlaba for a duck, Captain Knight (8) run out
Bosch also traps Beaumont (28) lbw & bowls Lamb (38) after England openers put on 65
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Lead by 43
Nat Sciver helps herself to three more. She's up to 118. What words can we even use for her anymore?
There are six balls left in the day's play. It's 18:07 BST and we've got through 99 overs. It's miraculous.
Here's the moment that Alice Davidson-Richards reached her century.
She's going to be watching this on repeat tonight.
Alex Hartley
Former England bowler on BBC Test Match Special
It has been a good day of Test cricket. I do fear that with only two days left, we may struggle for a result.
Lead by 40
Just a single from Tumi Sekhukhune's latest over.
There are two overs left in the day's play.
Chat has already turned to whether this game is heading for a draw already with two days gone - the forecast may influence that. England, with a lead of 40 at the moment, will surely look to be proactive in the morning.
Alex Hartley
Former England bowler on BBC Test Match Special
It would be a waste of a review. The bowler hardly appealed. It was more of a "pleeeease, can we have a wicket?"
Nat Sciver is just so good.
Anneke Bosch drops a little short and Sciver muscles through mid-wicket for a couple more.
That takes the stand above 200. Wow. The record for any wicket by England is 235. That's in reach.
There's a half-hearted appeal to end the over but Sue Redfern isn't having any of it. It did look a little high.
Alex Hartley
Former England bowler on BBC Test Match Special
Whatever team Alice Davidson-Richards is playing for, she brings a bundle of energy. There is always a smile on her face.
It's been a really impressive knock with the way she's been able to find the boundary through the covers. Just hit the bad balls.
Sciver 111, Davidson-Richards 106
Speaking to Ffion Wynne before the Test Alice Davidson-Richards said she was "emotional" about the call-up. Imagine how she must be feeling now.
She picks up four more from Tumi Sekhukhune and Nat Sciver takes a single.
The partnership is 198 now. Unreal.
Emily Windsor
Southern Vipers batter on BBC Test Match Special
What has impressed me is her technique. She's been just as good in defence as she has in attack.
Alex Hartley
Former England bowler on BBC Test Match Special
Davidson-Richards, take a bow! That is absolutely phenomenal! A hundred on debut. England were in so much trouble when she came in! Very, very special.
What an innings! A maiden Test century on debut for Alice Davidson-Richards!
England were 121-5 when she came to the crease and they were in real trouble but ADR has played brilliantly. She was patient to start and has gone through the gears as the evening session has gone on.
It comes up with another punched drive through the covers and there's a beaming smile on her face as she's embraced by Nat Sciver.
It comes up off 173 balls and she is the third women to score a century for England on Test debut after Lesley Cooke and Enid Bakewell.
What a special knock.
We seem to say it so often but Nat Sciver has been brilliant again...
Emily Windsor
Southern Vipers batter on BBC Test Match Special
Anya is giving it a nervous grab of the knees, she's making me nervous!
Lead by 24
Two dot balls end the over.
Alice Davidson-Richards look pretty calm. She's full of chat with Nat Sciver at the end of the over.
Anya Shrubsole
Former England bowler on BBC Test Match Special
I hate people getting near milestones. I love it - but I hated it because I get so nervous for them!
Alice Davidson-Richards is flying!
More width from South Africa and she twice crashes through point for four.
She's up to 97.
The nerves must be flying through her body.
Anya Shrubsole
Former England bowler on BBC Test Match Special
That's a great shot down the ground by Alice. She's driven the ball really well and that's another example.
We're seeing what can happen with that second new ball when you have two set batters in, it can be a good chance to score.
Lead by 16
Alice Davidson-Richards has looked really at home as her innings has progressed. She's not quite a direct replacement for Katherine Brunt because she's more of a batting all-rounder but she's got a real chance to make sure that spot is hers.
She picks up another boundary down the ground with a glorious drive.
She's edging towards that century...
Anya Shrubsole
Former England bowler on BBC Test Match Special
I wonder if there is anything else South Africa can try to get a wicket here. It feels like they are waiting for a mistake from the batters or a magic ball. They look short of ideas.
Lead by 11
Just a leg bye from Tumi Sekhukhune's latest over.
Eight overs left in the day, light and rain permitting.