Faf du Plessis demanded a ruthless performance and he got it when his bowlers dismissed Sri Lanka for 131, trailing by 295 on the first innings.
Given that his strike force had been out there for only 90 minutes and had bowled just 17 overs between them in the morning, as Sri Lanka collapsed from 80-4 overnight, he had no hesitation in enforcing the follow-on.
It paid immediate dividends when Kaushal Silva was beaten by Kagiso Rabada’s pace and bounce and gave Quinton de Kock an easy take.
They went in to lunch at 13-1, trailing by 282 and looking at defeat before the day is out, unless the expected rain arrives and eats into playing time.
There were some remarkable performances in the morning session, none less than the brilliant catch by De Kock to dismiss Angelo Mathews, diving to his right to snaffle the low catch just in front of Hashim Amla at first slip.
It was a moot point whether it could have carried the extra three metres to the ourstretched hands of Amla, but in the end it was irrelevant. It was the result of another perfect delivery from Rabada, which Mathews tried to defend on his toes. he had added just
There were two excellent debut wickets for Duanne Olivier, too, removing Rangana Herath with a pace-bowler’s dream delivery. It just kept rising at the hapless batsman, which he could only fend off, producing a high looping catch to Stephen Cook at short leg.
His second was more prosaic, angled away from Upal Tharanga, who had the highest score of the day at 24, to find the edge on its way to Dean Elgar at third slip.
The bowling was of the highest quality, even though the wicket did not provide as much spiteful movement as it did on the morning of day two, when South Africa were rolled out.
Philander started the rot with a snorter to Dinesh Chandimal in the third over of the morning; a ball he had to play and which shifted on to the edge and through to De Kock.
Wayne Parnell got into the act, too, removing Suranga Lakmal, who chipped to mid-off and then taking a great low catch of his own bowling to dismiss Nuwan Pradeep.
The wicket is not getting any easier and the Sri Lankan batsmen, who have shown little enthusiasm for a dogfight, know they will be in for a torrid time against the enthusiastic four-prong pace attack.
Photo: Lee Warren/Gallo Images
