South Africa slip to 88-6
Three wickets for Wood
Wood strikes with final ball of day
De Kock 32*, Elgar 26, Malan 15
England 400: Root 59, Pope 56
Broad 43 (28), Wood 35* (39)
Last-wicket stand of 82 off 50 balls
Nortje 5-110 - maiden five-wicket haul
Fourth Test, day two, Johannesburg
England lead 2-1 in four-Test series
Image source, Getty ImagesEngland could go about this in two ways over the final three days - enforce the follow-on or bat again - but they'll surely still win either way.
South Africa are still 312 behind with four wickets left.
Click here for full details of another great day for England or scroll down for reaction. We'll be back tomorrow from 7:45 GMT.
#bbccricket
Tim Carlisle: Mark Wood averaging 77 with the bat and 14 with that ball - how many all rounders are England allowed to play?
Mark Wood just loves taking wickets for England.
He has 3-21 and is eyeing another five-wicket haul.
Image source, Getty Images#bbccricket
Michael Champion: England need to hold back tomorrow or there will be calls for three-day Tests!
England bowler Chris Woakes, speaking to Sky Sports: "It has been a great day. The way the boys came out and managed to get 400 on board was a great start. 400 was a great score for us on that surface.
"You don't expect the last three wickets to get 120 runs. The boys down the order put in a shift. Taking the score from 320 to 400 is a big difference in this game.
"We have done right things with the ball as well. We saw them go to the short stuff pretty soon and our run-rate increased when the ball was still doing a bit from a good length. We tried to hit the right length, hit the bails and we know nicks carry here. We have done well. The ball swinging suits us but you still have to put it in the right areas.
"After the warm-up games I was hoping to get the nod but it went downhill [with illness]. It has been frustrating. The boys have played fantastic cricket so it has been hard to get back in [to the team]. But I took my opportunity and hopefully have done myself alright."
Niall O'Brien
Former Ireland wicketkeeper on The Cricket Social
It was a shoddy performance by South Africa with the ball and the batting was just spineless.
Jonathan Agnew
BBC cricket correspondent in Johannesburg
There was that moment when South Africa had a chance but were blown away by Wood and Broad slamming sixes all over the place.
South Africa's innings never got going; they have been just grinding along at two an over.
The thing we might not look forward to tomorrow is Joe Root inevitably batting on.
When England slipped to 269-7 this morning there was a chance they could be skittled cheaply but since then they have shown that they are just a better team than South Africa.
Vikram Solanki
Ex-England batsman on The Cricket Social
It's been the perfect day for England. Rightly so, Wood will take all the accolades but the bowling group put together a real partnership against an inexperienced batting line-up.
It already looks certain that England will win this match. They have been relentless with the ball. It has been dominant. One of the best bowling days I can remember for a while.
There are two completely different-looking dressing rooms at the Wanderers. South Africa coaches Mark Boucher and Jacques Kallis look as glum as can be - Kallis shaking his head in disappointment. The England backroom staff are on their feet applauding the players from the field.
Jonathan Agnew
BBC cricket correspondent in Johannesburg
England are absolutely delighted with that. It went very smartly to Denly. They've been all over South Africa.
The only time South Africa were in the game today was when England were 318-9 but that last wicket stand knocked the stuffing out of South Africa.
Nortje c Denly b Wood 6 (SA 88-6)
The perfect finish to a close to perfect day for England. Mark Wood squeezes out one last wicket, that of Anrich Nortje, on what turns out to be the final balls of the day.
Nortje squirts a catch to Joe Denly at fifth slip.
It's high fives all round for England.
Quinton de Kock walks down for a chat to waste a few more seconds...
There's no rush from anyone out there.
This Mark Wood over may be the last. De Kock edges just over his stumps.
Text 81111
Whenever England get beaten it's because the opposition is great but when we win it's because the opposition is poor.
Steve, Chelsea
Trail by 313
I'm slightly surprised to read that Quinton de Kock has the most runs of any player in this series. The next four names on the list are all Englishmen, however, and that tells the story of the series. De Kock has been untroubled again today.
There's a fella with a sign reading 'coach put me in' in the stands. He's probably closer to a call-up than he thinks.
De Kock 26, Nortje 6
Another over survived by Nortje. Give that man the freedom of Johannesburg.
There's another streaker. Not even a hint of a smirk from big Anrich.
Eight minutes of play remain.
Text 81111
It's always nice to win away in a Test series, but in my almost 20 years of following cricket this is by far the poorest South African team. I feel for Nortje!
Jack, St Albans
Trail by 319
I absolutely love Anrich Nortje. He plays a Ben Stokes bouncer about as uncomfortably as it is possible to do so with both feet in the air, his back arched and bat waving out in front of him but he keeps it down, glares back at Stokes and then gets back on with his job.
He should get some sort of national award for his efforts in this series.