With the series level at one apiece, everything now hinges on the final match back in Cape Town next Saturday.
The Springboks were worthy winners, producing two delightful second-half scores after a first 40 minutes which were mind-numbingly ferocious.
Makazole Mapimpi and Lukhanyo Am were the try scorers but it was the halfbacks, Handre Pollard and Faf de Klerk, respectively, who were the creators, although there was more than a hint doubt as to whether Am had grounded the ball properly.
This was a chastening experience for the Lions who must now regroup and drag their aching bodies into a third and final Test match.
There was a yellow card on each side, with Scotland wing Duhan van der Merwe sent to the sin-bin for a trip on Cheslin Kolbe. The South African followed him in there a minute later after tackling Conor Murray in the air.
Passions had been inflamed by the extraordinary build-up to the game and it took only two minutes for emotions to spill over. The players came together and it was an early test for referee Ben O’Keeffe whose credentials had been questioned by Rassie Erasmus in the South African director of rugby’s curious home movie.
O’Keeffe told both captains that such behaviour would not be tolerated. Alas, it wouldn’t be the last time the New Zealander was required to speak to the skippers.
Chris Harris, the only Test debutant in the Lions ranks, put down an early marker with a huge hit on Am. It set the tone for a hugely physical encounter, although there was a glimpse of Kolbe’s dancing feet as he skipped past Dan Biggar.
Play was called back because the Lions had gone offside and Pollard cashed in to give the Springboks a 3-0 lead.
In the midst of the move van der Merwe had dumped Pieter-Steph du Toit on the ground with a tackle which looked illegal and was certainly late. The big Scotland wing got away with this one but du Toit never recovered from the shoulder injury he sustained as he landed and had to leave the field midway through the half, replaced by Kwagga Smith.
As expected, the ball was spending a lot of time in the air and Biggar unleashed a huge up and under as the Lions made their first incursion into the home side’s 22. Willie le Roux spilled it and the tourists turned the screw. Jasper Wiese’s no-arms tackle on Luke Cowan-Dickie gave Biggar the opportunity to draw the Lions level and the stand-off followed it up with a second penalty after Kolbe’s head-first tackle.
The Lions had edged ahead 6-3 and Pollard missed the chance to even things up when he was uncharacteristically wayward with a penalty attempt.
The fun and games started midway through the half when van der Merwe foolishly tripped Kolbe as the winger attempted to gather the ball. If you were being generous you could argue it was a mistimed attempt to kick the ball, but O’Keeffe correctly decided it was worthy of a yellow card.
With the former Edinburgh man in the sin-bin, South Africa might have thought this the perfect opportunity for Kolbe to exploit the one-man advantage. Unfortunately for the Boks, the winger quickly joined van der Merwe on the naughty step.
Murray was taken out in the air by Kolbe, sparking an angry reaction from the Lions, with much shoving and grabbing. Kolbe had his eyes on the ball but Murray landed awkwardly and the yellow card was merited.
After both captains were spoken to once again a game of rugby briefly broke out as the Lions produced a lovely passing move which was halted by a knock on.
Pollard restored parity with a monster penalty but the Lions thought they had made the breakthrough five minutes before half-time. Murray tried a delicate kick into the danger zone for Robbie Henshaw but as the Irish centre tried to ground the ball he was smothered by the collective force of Siya Kolisi, Smith and Damian de Allende.
O’Keeffe didn’t think it was a clear grounding and the TMO agreed. Play was called back for an earlier offence and Biggar ensured the Lions went in at the break 9-6 ahead.
Momentum quickly shifted back in favour of South Africa who began the second half with the same ferocity but added precision. The souped-up Springboks knew this was do or die and produced two tries in 14 minutes to turn the game on its head.
Both were finely crafted scores, lifting the match from its attritional funk. Pollard was the architect of the first, shaping to pass but then kicking wide to Mapimpi who caught cleanly and squeezed through the attempted tackles from Anthony Watson, Stuart Hogg and Jack Conan.
Pollard missed the conversion but the stand-off deserves great credit for creating the breakthrough try.
Biggar attempted to put the Lions back in front but his penalty attempt hit the post and bounced back on the pitch.
South Africa took full advantage and increased their lead on the hour mark with their second try, although there was a whiff of controversy about it. De Klerk was the creator this time, kicking through for Am who pounced on the ball just before it went dead.
O’Keeffe thought it was good and so too did the TMO but only after several replays as it was questionable whether Am had control of the ball as he tried to ground it.
The Boks were flying and Pollard’s conversion and a penalty ten minutes later increased their lead to 21-9.
The stand-off then added two late penalties to stretch the margin of victory to 27-9.