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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Alex Hartley
Former England bowler on BBC Test Match Special
I'd not even noticed that the boundaries were bigger because you're still getting value for your shots. When you beat the in-field, the ball is going away quickly. I don't see why we can't play with bigger boundaries in Test cricket?
Trail by 24
Another maiden from Marizanne Kapp.
England won't mind that though, it is about seeing her off with this new ball.
Phil Long
BBC Test Match Special statistician
There were 21 overs in that half-session from tea until drinks and England scored 84 runs.
Nat Sciver has followed up her highest ODI score in the World Cup final with her highest Test score.
Alice Davidson-Richards has played really nicely.
Here are the best shots from her maiden half-century in Test cricket.
Alex Hartley
Former England bowler on BBC Test Match Special
England are in a strong position now. It was South Africa's day up until tea but these two have batted well.
Trail by 24
Really productive over for England.
Anneke Bosch drops short and Alice Davidson-Richards whacks it the cover boundary before she picks up two more through the on-side.
More width and Davidson-Richards crashes it away again.
She's up to 67 now. Is a debut ton on the cards?
Alex Hartley
Former England bowler on BBC Test Match Special
Although Kapp has not taken any wickets today, she's created a lot of pressure.
Trail by 34
Marizanne Kapp starts with a maiden.
She's only gone for 18 off her 13 overs so has been extremely economical so far but England will have been happy with how they've played her.
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Interestingly, Nat Sciver and ADR were at school together. This is surely a record for the highest England partnership by players who attended the same school...
Dave, Newcastle
Image source, Getty ImagesTrail by 34
Lovely stuff.
A gentle push from Alice Davidson-Richards brings her four more runs through mid-on.
That's got to be up there with her best shot today.
Anneke Bosch will get first go with the new ball.
She's taken three wickets so far - she's been impressive.
Alex Hartley
Former England bowler on BBC Test Match Special
I would be giving the new ball to Bosch and Kapp.
Trail by 38
Nat Sciver and Alice Davidson-Richards share singles again.
Time for the new ball. Unsurprisingly South Africa take it straight away. They need wickets with it.
#bbccricket
Jack Rule: What a pick Alice Davidson-Richards is proving to be in this England team. Definitely going to make team selection through this summer a lot more difficult.
Trail by 40
Nat Sciver and Alice Davidson-Richards exchange singles after the boundary.
South Africa look like a side that need the new ball. It is six balls away.
Melissa Story
BBC Test Match Special
This is when we get to the point when no one is allowed to move in the commentary box because of all the superstitions.
Oh, Nat Sciver. That is gorgeous.
The vice captain comes down the pitch again, goes into out, and drives over mid-off for a one-bounce four.
A lovely shot to move into the 90s.
Anya Shrubsole
Former England bowler on BBC Test Match Special
This has been a significant innings from Alice and she's played such a fantastic supporting role. It's been brilliant from her and she's batted with composure and a really clear method and she's really deserved that fifty.
Eng 236-5
What a way to start your Test career by Alice Davidson-Richards.
England were under real pressure when she came to the crease at 121-5 but she has combined brilliantly with Nat Sciver to guide the hosts out of trouble.
Can she go on and guide England into a lead?
Emily Windsor
Southern Vipers batter on BBC Test Match Special
How much is that next one run on Alice Davidson-Richard's mind?