Graham, this is excellent chat. What other cricketing terms are misleading? The nightwatchman doesn't stay out there all night, does he?

Thanks, Justin. Yep, 38 overs in the rest of the day does seem like a lot. I rather fancy that the light will intervene before we complete them all.

JT: I'd take losing the last test and winning the series every time, better than the alternative.

I'm hearing that play can continue until 16:18 GMT today - there are 38 overs still to bowl in the evening session. Stephan Shemilt will talk you through them...

Paul Huxley: Re Ben Prior (98 overs) - 6th ranked England not as ruthless as all time greatest team? Really?

England 318-8 (98 overs) - trail by 157

Batsmen: Moeen 45* (78), Broad 4* (14)

Fall of wickets: 22-1 (Hales 15), 78-2 (Compton 19), 177-3 (Cook 76), 208-4 (Root 76), 211-5 (Taylor 14), 211-6 (Bairstow 0), 252-7 (Stokes 33), 295-8 (Woakes 26)

Bowling figures: Abbott 19-9-36-0, Rabada 26-6-101-6, Piedt 23-4-74-0, Morkel 23-4-72-1, Elgar 4-0-13-0, Duminy 3-0-14-1

South Africa 475: De Kock 129*, S Cook 115, Amla 109; Stokes 4-86

Full scorecard

Francis Edwards: Doesn't matter how deep you want to pack your batting, quality over quantity. Five players in this team have question marks.

Benjamin Fox: With this England team, it's got to be demoralising for the opposition with Moeen is at eight and a Test centurion in Broad at 10.

And that's your lot for the afternoon. Broad plays out a Piedt maiden, tucks his bat under his arm and marches off with Moeen, who is unbeaten on 45. Cup of tea, anyone?

Ben Prior: England just can't win the last game of a series. We are just not as ruthless as Australia were in their prime!

Mike Bell: Cheer up chums. Get to 350, whip 'em out for 160, win the match late on day five. Why the long faces?

Broad is doing a good job of getting off strike, collecting his fourth single to keep England moving along before Moeen tickles four fine. Although England have lost eight wickets, the run-rate is a healthy 3.27 in the innings. One more over before tea.

I know Duminy got the wicket of Woakes, but I can't help thinking South Africa have released the pressure a little by employing two spinners here - especially against Broad and Moeen, both of whom have shown weaknesses against pace in the past. As I type, Broad bottom-edges a swipe at Piedt. Lucky to get away with that.

Michael Vaughan
Ex-England captain on BBC Test Match Special

"That is a tremendous shot by Moeen Ali. It's not that bad a ball but he opens his blade and guides it into space with his wrist-work. He's playing really well."

Duminy errs in line ever so slightly and Moeen late cuts for four. Wonderful timing. Even better placement. Ten minutes until tea.

Max Mclean: Is Moeen the best number eight in Test cricket right now?

Can Morkel polish off the tail? He'll have to get past Moeen first. The left-hander drives through mid-off's hands for four on the up, then rocks back to pull for another boundary.

Geoffrey Boycott
Ex-England batsman on BBC Test Match Special

"This has been a splendid performance by South Africa. They have got everything dead right here. Really, really good cricket. Apart from James Taylor's shot, this isn't necessarily bad from England."

Stuart Broad in at number 10. England on the brink of conceding a hefty first-innings advantage to South Africa.

Michael Vaughan
Ex-England captain on BBC Test Match Special

Image source, Getty Images

"Well that is unfortunate. It's a good angle by JP Duminy round the wicket. Chris Woakes played well considering he hadn't featured for three and a half weeks."