Is it a no-ball?

Now then. South Africa are pretty sure about this. Joe Root trying to hook Kagiso Rabada, in a tangle. Caught at slip. Not out. Dean Elgar not convinced.

Andrew Samson
BBC Test Match Special statistician

Root's fifty from 89 balls. He has scored fifties in each of his last seven Tests and has passed fifty in each of the five Tests he has played against South Africa.

Joe Root reaches a half-century in his first match as captain, his 39th score in excess of 50 in 54 Tests. He's had two lives, a chance to fine leg and a drop at gully, but he's steadying England after that morning wobble. Is this a sign of things to come? Captain Root the totum of the England batting?

Daniel Potter‏: What's the obsession with Stoneman? He's 30 - why give debuts to 30+ when we have so many great youngsters? Lions are waste of time.

Maharaj v Stokes once more. You can just feel the Stokes urge to get after the left-arm spinner, to hit him to Euston Station. He eventually settles for a single down the ground. Still Root waits for that half-century, but a single means he'll have 49 and the strike in the next over.

Andrew Samson
BBC Test Match Special statistician

Stokes faced 21 balls in a row. The 50 partnership has come from 84 balls.

It's been all Ben Stokes since lunch - literally. He's taken most of the strike. Joe Root has been made to wait to complete his half-century, missing out when Rabada drifts down the leg side. The fifty partnership is up - Stokes has 32 of them.

Image source, Reuters

Geoffrey Boycott
Ex-England batsman on BBC Test Match Special

I'm not sure if I was captain I'd like to be bowling spinners that don't turn. If they bowl at Stokes and it isn't doing anything, he isn't going to hang around, he is going to wallop it.

Close!published at 14:28 British Summer Time 6 July 2017

14:28 BST 6 July 2017

Eng 125-4

Stokes again! He's going after Maharaj once more, but this time almost comes a cropper. Mid-on is three-quarters of the way back. The ball goes straight up, with JP Duminy running back, trying to grab it as it drops over his shoulder. It evades his despairing dive, but that is ill-judged from Stokes.

Vic Marks
Ex-England spinner on BBC Test Match Special

If Woakes had not got injured, would they have gone in with five seamers? I think there was an element in selecting Dawson of not wanting Stuart Broad or Toby Roland-Jones batting at number eight.

Ben Stokes is illuminated by flashes of yellow. Spikes, pads, gloves and bat stickers all have the colours of a high-viz jacket. Anyone would think it was planned. The buttons on his shirt are open, revealing a healthy amount of chest. He seems like a man ready to be entrenched in the work that lies ahead. A maiden from Rabada.

Geoffrey Boycott
Ex-England batsman on BBC Test Match Special

It looks flat now. This morning there was a tiny little bit of seam movement but I said once the shine had gone it would be nice to bat. It wasn't a four wickets down in the morning pitch.

Eng 118-4published at 14:19 British Summer Time 6 July 2017

14:19 BST 6 July 2017

Oh, yes! Ben Stokes serves notice that he is not going to let Keshav Maharal settle. Two balls from the left-srm spinner and Stokes is down the track, lofting iron-straight into the members' area. That's on way to ensure the old boys are still awake after their lunchtime glass of port.

Jonny P, London

South Africa have taken four wickets, but they are also minded to defend. For both of these batsmen there is a man back on the square leg boundary. It's hot, but Root is still batting in his omnipresent sleeveless sweater. The skipper, hunting a half-century in his first match in charge. tucks a couple off his hip.

Vic Marks
Ex-England spinner on BBC Test Match Special

There are two schools of thought for South Africa against Stokes. One is that the tail is in sight so you might attack, attack, but the other, after that mauling he gave them in Cape Town, is to keep him quiet.

That's the shot of the day so far. Morne Morkel overpitches, Ben Stokes leans forward into the straightest of drives, just avoiding the non-striker's stumps on its way to the boundary. Joe Root didn't really enjoy it, mind. He's already been run-out backing up once this summer. As the ball went past, Root put a hand to his chest in relief.

Vince Kenny‏: Ted Milnes - They probably struggle with the ridiculousness of your statement. They are not alone.

Further information on the next England kit. The buttons around the neck and collar are a dark colour. It looks like they ran out of white ones and had to use whatever they could find. There's a slash from Stokes, in between second slip and gully, bringing up the England 100. Warm applause from those who have made it back to their seats.