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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Georgia Elwiss
England all-rounder on BBC Test Match Special
These two are both aggressive but technically correct players. They'll need to be patient and build a big partnership because once you get in on this pitch, runs can come easily.
#bbccricket
Hertingfordbury CC: Tabloid hacks already have tomorrow's headline "Bish Bash Bosch"
Sciver 29, Davidson-Richards 4
Sciver is irritated with herself for missing out on a full toss but is quickly able to make up for it, pulling a long hop from Bosch away in front of square for four. Played with real conviction.
Amy Jones won't want to see this again - but you can...
A first Test wicket for Nonkululeko Mlaba as she knocked over Jones with a straight one.
Phil Long
BBC Test Match Special statistician
England have lost three wickets for 39 runs in the 16 overs since lunch.
Alex Hartley
Former England bowler on BBC Test Match Special
I used to think my middle name was 'Andra'. As in, Alex Andra Hartley.
So if they did that to me they'd call me Aah.
Henry Moeran
BBC Test Match Special
Why do they call her ADR?
Maybe because they're her initials, Henry.
An eventful first hour after lunch and South Africa will be thrilled with how it has gone. Three wickets, including the big one of Heather Knight.
Runs! Four of them!
Alice Davidson-Richards is off the mark in Test cricket, opening the face of the bat and squeezing the ball down to third.
The pressure continues to build on England with a fourth maiden in the last five overs. Bosch is getting the ball to swing away from Sciver nicely and the England batter remains watchful.
#bbccricket
Thomas Laver: Maybe this is just England's ploy to lull SA into a false sense of security before ADR becomes our Kapp and scores a quickfire hundred, taking them all by surprise!
Another maiden. Mlaba to Davidson-Richards and South Africa are putting the squeeze on England.
Alex Hartley
Former England bowler on BBC Test Match Special
This is my sixth day of watching Test match cricket in a row. I just love it.
Maiden over from Bosch as Sciver defends solidly. She will be well aware just how important her wicket is now. She'll also know that England cannot just stand still. When does she make her move?
Phil Long
BBC Test Match Special statistician
England were 61-0 before the lights came on at just after midday. It made quite the difference.
Alex Hartley
Former England bowler on BBC Test Match Special
Alice Davidson-Richards is a fine batter and she's got a simple job here - just stick with Nat Sciver.
Melissa Story
BBC Test Match Special
Marizanne Kapp was that anchor for South Africa and the innings was built around her.
It feels like Nat Sciver has to fulfil that same role here for England.
Alice Davidson-Richards comes in on Test debut. Now would be a good time to really make a name for herself in international cricket...
Alex Hartley
Former England bowler on BBC Test Match Special
She's just missed a straight one! It's not turned, it's just held its line and Amy Jones has gone for a standard forward defensive and just missed it.
Jones b Mlaba 0 (Eng 121-5)
Bowled her! England are in all sorts now! Not much turn at all from Mlaba, Amy Jones has just played down the wrong line.
Not a dismissal she will want to see again.