Centurion - The new-look Proteas seam machine, led by a superb Vernon Philander, shifted through the gears at SuperSport Park on Friday to leave the hosts ahead in the first Test against England.
It was an action-packed second day, with a total of 15 wickets falling as South Africa's bowlers put the Proteas in firm control before another top order collapse allowed England back into the contest.
Philander, who will retire from international cricket at the end of the series, reminded South Africans of exactly what they will be missing by carding stunning figures of 4/16 from 14.2 overs.
The 34-year-old showed exactly why he has long been considered one of the world's best new ball bowlers in the format and further cemented his status as one of South Africa's finest.
Oozing panache and class, Philander bowled with near-unbelievable accuracy and control, moving the ball both ways on a Centurion surface that continues to test even the very best batsmen involved in this fixture.
From start to finish, he was impeccable, and his immaculate line and length meant that England's batsmen were left with no option but to try and survive.
That was evident by the fact that it took 34 balls - 5.4 overs - before Philander conceded a run off the bat.
Kagiso Rabada (3/68 in 15), Anrich Nortje (2/47 in 12) and debutant Dwaine Pretorius (1/23 in 8) combined to see England bowled all out for 181, leaving them 103 short of the South African first innings total of 284.
As impressive as the South Africans were with the ball, however, the top order was disappointing once more.
At stumps on day two, the Proteas had slipped to 72/4 in their second innings, giving them a lead of 175 going into day three.
Rassie van der Dussen (17*) and nightwatchman Nortje (4*) will be at the crease when day three gets underway on Saturday.
Friday started with Philander and Nortje (0*) walking out to bat for South Africa's final wicket, but the pair could only add another 7 runs before Philander (35) edged Stuart Broad through to Jos Buttler behind the stumps to bring the innings to a close.
It was perhaps not the total the Proteas would have hoped for at the start of the match, but what followed showed that it was more than competitive.
After a quick turnaround, the Proteas seam attack then got to work and Rabada thought he had a wicket with the first ball of the innings - as James Anderson had done for England the day before - when Rory Burns was given out caught behind. A review, however, showed that he had clipped his front pad instead.
They didn't have to wait long, though, and Philander struck with the first ball of his second over when he did have Burns (9) caught behind with a probing delivery that asked all the right questions.
Rabada was on the board in the very next over when opener Dom Sibley (4) was caught behind. The decision was originally given 'not out', but Du Plessis reviewed immediately, and that action alone controversially prompted Sibley to walk to leave England in early trouble at 15/2.
While Philander bowled 5 maiden overs in a row, Rabada begin to slip slightly as England recovered with an array of scoring shots through Joe Root and Joe Denley.
Nortje was also expensive early on and the visitors built a much-needed 55-run stand for the third wicket. It looked like both batsmen were set, but it was Philander who got the Proteas moving again with the key wicket of Root (29) with just the seventh ball of his second spell.
The skipper had tried to be proactive and use his feet, but all he could do was tamely edge through to De Kock.
That brought Ben Stokes to the wicket and, once again, England recovered in the form of a 74-run stand between their 2019 World Cup hero and Denley for the fourth wicket.
Rabada and Nortje continued to struggle, and the breakthrough came instead through allrounder Pretorius, who had stemmed the flow of runs.
It was De Kock again who took the catch, which also had to be reviewed after Denley (50) was originally given 'not out', and England found themselves 142/4. That was where the collapse began, with the visitors losing their last seven wickets for just 39 runs.
After toiling without any reward, Nortje finally had his moment when he dismissed Jonny Bairstow (1) and Stokes (35) in quick succession. Stokes was a massive blow for England, having looked in dangerous form during his 87-minute stay at the crease.
Rabada then had Sam Curran (20) neatly pouched by Zubayr Hamza at short leg before Philander nicked off Jos Buttler (12) for what would be De Kock's sixth catch of the innings - a new record for a South African against England.
Philander appropriately finished the innings by knocking back the top of Jofra Archer's (3) off-stump before the Proteas jogged off the Centurion turf in high spirits.
That optimism was short-lived, though, thanks to another South African top order collapse.
Aiden Markram completed another miserable Test when he was out LBW off James Anderson for 2 in the first over of the innings while Zubayr Hamza (4) was caught behind down the leg side off Stuart Broad.
When Dean Elgar inside edged Archer through to Butler to fall for a brisk, promising 22, the Proteas had slipped to 29/3 and the Centurion crowd had witnessed the last 10 wickets in the Test match fall for just 68 runs.
Archer wasn't done yet, and when he had a hooking Du Plessis (20) caught on the fine leg fence, England were smelling blood.
There was a moment of controversy right at the end of the day when Archer bowled back-to-back beamers at Nortje, causing speculation that the umpires could remove him from the attack on Saturday.
The second full toss, however, was not called a no-ball and Archer now looks set to continue.
Scores in brief:
SA 284 (De Kock 95, Broad 4/58, Curran 4/58) and 72/4 (Elgar 22, Archer 2/37)
England 181 (Burns 50, Philander 4/16, Rabada 3/68)
SA lead by 175 runs with 6 second-innings wickets in hand