England moved into a commanding position in the first Test at Kingsmead on a miserable day for South Africa that saw Dale Steyn suffer further injury woe.
After South Africa had been dismissed for 214 to concede a lead of 89, despite Dean Elgar's unbeaten 118, Steyn was forced to leave the field two balls into the seventh over of England's second innings.
A shoulder strain was swiftly diagnosed, but the leader of South Africa's attack - who missed the bulk of the Proteas' previous series in India due to a groin problem - nevertheless returned and attempted to bowl once more, only to again pull up mid-over.
The absence of the world's number-one ranked Test bowler left the hosts short on bowling options and their cause was further damaged by a trio of drops as England progressed to 172-3 and a healthy lead of 261.
Nick Compton was given two reprieves on his way to 49, while AB de Villiers - the guilty party for the second of those chances - also spilled Joe Root on six and watched England's number four reach stumps unbeaten on 60.
With two days still remaining, England appear well placed to move ahead in the four-match series, while doubt will surround Steyn's availability for the second Test, which starts on Saturday in Cape Town.
Elgar's admirable show of defiance continued on Monday as he became the first South African to carry his bat since Gary Kirsten in 1997, but there was little support for the gritty opener.
After Stuart Broad (4-25) had followed up his excellent work on the previous day by inducing Temba Bavuma (10) to chop on without addition to South Africa's overnight score of 137-4, Moeen Ali (4-69) accounted for JP Duminy (2) and Kyle Abbott (0) in successive overs.
Steyn (17) offered resistance as he accompanied Elgar to his fourth Test hundred, brought up from 211 balls, but the former became Moeen's fourth victim when a wild heave provided Chris Woakes with a catch at mid-off and Steven Finn (2-49) quickly wrapped up the innings with the second new ball.
England skipper Alastair Cook again fell cheaply, lbw to Dane Piedt (2-69) for seven, but by that stage South Africa had been significantly hampered by Steyn's initial exit.
An England wobble before tea saw Alex Hales (26) hole out to long-on off Piedt prior to Compton and Root surviving chances to Elgar and De Villiers respectively - Morne Morkel the unlucky bowler on each occasion.
Morkel (1-19) did finally remove Compton for 49, two balls after De Villiers had spilled a second opportunity behind the stumps, but Root pressed on alongside James Taylor (24 not out) to leave the hosts in deep trouble.