AB de Villiers ask for another lightmeter reading in the hope that it has brightened. It hasn't. Piedt continues. If De Villiers decided that he didn't want his nice new ball being scuffed up tonight, he could bring the pacers back now, get off for the light then come back fresh in the morning.

Geoffrey Boycott
Ex-England batsman on BBC Test Match Special

"Elgar's a lollipop bowler, he just tosses the thing up. These are terrible appeals."

It is that dark? It actually looks to have just brightened up. Then again, if it means they don't have to face Rabada, England would bat on the dark side of the Moon. Twice left-armer Elgar shouts against Root, but both times it's missing the leg stump. Nine overs left in the day.

Geoffrey Boycott
Ex-England batsman on BBC Test Match Special

"This is better light than when Amla was right at the end of his innings, when the rain was coming. It got darker than this and England still had their seam bowlers. I really don't understand the light rule..."

Image source, Reuters

The umpires chat with AB de Villiers. They've told him that it's too dark for the pacers so he must go to spin. Kagiso Rabada off, Dean Elgar on.

Jon Ternent: Good grief, what a pathetic parade from #England, external - where's the fight?

Peter Goodwin: Death, taxes and England openers collapsing. Three things that are certain in life.

Firmin Fredericks: England starting the T20 early I see...

Should be a fourth wicket! Joe Root is reprieved, Quitnon de Kock fluffs his lines. Root is beaten in the air by Dane Piedt and, trying to turn on the leg side, walks past one. It hits De Kock and crashes to the ground. Root is miles out, but can get back.

Meanwhile, the lightmeter is out...

It is raining. Only lightly, but the wet stuff is definitely falling. There is also a Kagiso Rabada storm blowing, a lithe, easy-actioned, pacy whirlwind that is sweeping of England before it. I'm going to stick my neck out and say that it's tough for England to win it from here.

Mark Boucher
Former South Africa wicketkeeper on BBC Test Match Special

"Taylor looks like he wants to play. South Africa won't mind that. It's not about the runs for them now; it's all about the wickets." 

The Barmies switch to Singing in the Rain. The wet stuff is needed for England, who look like they could suffer further losses with every delivery bowled. Taylor is beaten by a Piedt off-break. There are still 12 overs left in the day, light permitting.

Like Augustus Gloop and the river of chocolate, Compton just couldn't resist. Rabada, who now has nine in the match, hung out the drive ball, and the England number three happily wafted and edged. As for the review, staggering. It almost took part of the bat with it. Yet another batsman who needs runs, James Taylor is out at number five. The Barmy Army trumpeter plays the Great Escape. Can they get Steve McQueen to bat?

Mark Boucher
Former South Africa wicketkeeper on BBC Test Match Special

"What a fantastic bowling change by AB de Villiers! Whether it was forced by injury to Kyle Abbott or not, he'll take the credit. 

"South Africa will fancy their chances of taking another four or five wickets here. It doesn't look like they'll be needing tomorrow's last session."

Another? It's Kagiso Rabada again! Surely Nick Compton is caught behind? He thinks he's hit the ground. He asks for another look, but the whole ground thinks he's out... 

I bet Compton and Root are absolutely delighted that Morkel has been taken off. It's dark, the ball is new, your nipples were being used as target practice, yet South Africa have gone to the offie. There's a touch of turn, but not as dangerous as Morkel. The only thing I can think of is that Abbott has decided one over is enough and another seamer has come from the other end.