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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Anya Shrubsole
Former England bowler on BBC Test Match Special
They've rotated the strike very well and put away anything that has been offered. They're taking advantage of the inexperienced South African bowling attack and they could be on for a really good opening partnership here.
Another change of bowling as Anneke Bosch bowls her first over and Emma Lamb plays a perfect straight drive down the ground for three more.
Time for a drink. An excellent first hour for Lamb and Beaumont.
South Africa need to find a wicket or build some pressure with dot balls because England are accumulating runs with ease at the moment from too many loose deliveries.
Shabnim Ismail is such a loss for this Test. It would have been great to see her steaming in.
Anya Shrubsole
Former England bowler on BBC Test Match Special
Emma Lamb is really good with anything outside off stump either cutting or driving. She loves it around there and it's brought her some lovely boundaries. We saw Kapp capitalise like that yesterday and Lamb is doing the same.
Alex Hartley
Former England bowler on BBC Test Match Special
These two look very comfortable at the crease. There's lots of communication and reassurance and that's something they both like to have out there. They're talking lots and seem to be really enjoying it together.
Tumi Sekhukhune, who bowled one over earlier to allow the openers to switch ends, is back into the attack.
She overpitches slightly and is drilled down the ground by Tammy Beaumont for three more before Lamb smokes another cover drive for a sublime boundary.
These two are setting a lovely platform for England with a 50 partnership.
Alex Hartley
Former England bowler on BBC Test Match Special
That's Emma Lamb's first boundary in Test cricket and she's got a big grin on her face.
Lamb 18, Beaumont 21
England just starting to dominate a little more as Emma Lamb crunches one off the back foot for four before placing a glorious cover drive for the same result.
A great over for England and Lamb, who is easing into her work very nicely.
Alex Hartley
Former England bowler on BBC Test Match Special
I don't think South Africa will be panicking but they need someone else on the leg side or bowl a bit more outside the off-stump. It's just too easy for Tammy Beaumont at the moment.
It certainly doesn't look like ice cream weather.
The players look like they'd love a hot chocolate, though.
Marizanne Kapp makes a rare error by dropping one short and Tammy Beaumont crunches it away for four. Kapp then leaves the field at the end of her over - hopefully just a toilet break or something and not an injury.
That would be a huge loss.
Alex Hartley
Former England bowler on BBC Test Match Special
The thing is with ice cream is that it's just versatile and you can have it in so many ways. Whatever the weather you can have one. I'll be more than happy to get someone an ice cream here today if they want one.
It's a real test of patience out there for both teams at the moment.
South Africa would have certainly wanted a wicket by now, but they have bowled tightly and haven't let England run away with it.
It feels like something's going to give soon - but from which side?
Tammy Beaumont has started carefully, playing simple cricket by blocking the good balls and whacking the bad ones.
Easy game, right?
Alex Hartley
Former England bowler on BBC Test Match Special
The first slip needs to come forward - that is a genuine edge, but she is miles behind the wicketkeeper and it has dropped well short.
Edged! And drops short of slip! Beaumont survives again.
Those are the first real signs of either of the England openers looking in trouble. And who's caused it?
Marizanne Kapp. Obviously.
Image source, Getty ImagesAlex Hartley
Former England bowler on BBC Test Match Special
There we go... one from one from today and I got a couple yesterday. I couldn't count to six though... I'd lose count.
A quick game is a good game, I'd be one of those. I couldn't think of anything worse than being an umpire - have you seen how cold it looks out there?
A thick inside edge saves Beaumont.
Anna Harris is having a fine Test match here.
Now then!
Tammy Beaumont has been struck on the pad, Kapp likes it ... umpire Anna Harris doesn't.
They go for the review. Going down leg perhaps? Or has she nicked it?
Runs.
Tammy Beaumont times a lovely clip through mid-wicket off Nadine de Klerk that races away to the boundary.
There's not as much swing out there as England - and Lauren Bell in particular - were able to find yesterday.
Alex Hartley
Former England bowler on BBC Test Match Special
South Africa really need a square leg - they've got a very aggressive field at the moment.
A maiden from Kapp, including a first sight of the short ball that Emma Lamb sways nicely out of the way from.
Kapp said this morning that striking with the new ball would be crucial. England have negotiated the early threat very nicely.