Then it was the turn of the bowlers, led by Wood, as England pushed for a third successive win in a series which they lead 2-1.
“To get 400 was a great start,” said England all-rounder Chris Woakes, who made a successful first appearance in the series, scoring 32 then taking one for 16 in ten accurate overs.
“The way we bowled was fantastic. We found the right length on this surface. We know from history that there is bounce and carry so we want to get guys on the front foot as much as possible.”
South Africa finished the day still 312 runs behind, with Quinton de Kock (32), their only consistent batsman during the series, seeking to give the innings some respectability on Sunday.
Wood made the first breakthrough when he had Pieter Malan caught behind for 15.
He followed up with the wicket of the recalled Temba Bavuma, then finished the day on a high when nightwatchman Anrich Nortje was caught at gully in the last over of the day. He had figures of three for 21.
Sam Curran, Ben Stokes and Woakes picked up a wicket each.
England’s total was built around three big partnerships.
The first two, 107 for the first wicket between Zak Crawley and Dom Sibley and 101 for the fifth wicket between captain Joe Root and Ollie Pope, were compiled by recognised batsmen.
The last wicket stand probably hurt South Africa the most.
Wood and Stuart Broad, batting at numbers 10 and 11, hit seven sixes between them and put on 82 off only 50 balls.
Toothless South Africa
“I’m still a bowler but it’s nice to slog a few,” said Wood.
“I was probably happier with playing properly against Nortje, who was pretty quick. I was pleased to get through that.”
The Wood-Broad stand was devastating for South Africa as England turned a respectable total into one which by the end of the day looked too big for the hosts, who have yet to make 300 in an innings in the series.
South Africa’s bowling, with the exception of Nortje, was largely toothless.
Nortje bowled tirelessly at high pace and took five for 110, his first five-wicket haul in Test cricket.
“It’s nice to get it,” said Nortje. “I’ve been thinking about it a long time and to finally do it is a bit special.”
But Nortje said his personal achievement was overshadowed by the poor position of his team.
“We’ve got quite a few new players. We’re trying to learn as much as possible. It’s not going to happen overnight.”
Nortje ended the century stand between Pope (56) and Root (59), dismissing both batsmen after the pair had dominated the first hour of play, adding 66 runs to England’s overnight total of 192 for four.
Thanks largely to Nortje, England were reduced to 318 for nine.
Then came 41 minutes of mayhem as Wood and Broad indulged themselves against some mediocre bowling when Nortje was out of the attack.
Captain Faf du Plessis resorted to placing most of his fielders on the boundary but Wood (35 not out) and Broad (43) either hit over them or found the gaps.
In contrast, South African openers Dean Elgar and Malan could only score 11 runs in 12 overs before tea as they made a cautious start to their innings.
They lifted the tempo after the interval but Wood’s pace undid Malan to end an opening stand of 29. It proved to be South Africa’s biggest partnership of a miserable day, while England left the field in high spirits.