The first half was scrappy and error-strewn from the tourists’ point of view but they came out reinvigorated after the interval, forcing the hosts into conceding a string of penalties which allowed the Lions to turn a 12-3 half-time deficit into a five-point win.
Luke Cowan-Dickie got the visitors’ only try and Faf de Klerk did likewise for South Africa but Dan Biggar’s accuracy with the boot secured the triumph.
It took the tourists until the 63rd minute to get their noses in front but once ahead, they stayed there.
They are now one-nil up in the three-Test series and can clinch it with another win next Saturday back in Cape Town.
The late inclusion of Rory Sutherland in the starting XV took the number of Scots in the side to four, the most in a Lions Test team since 1993 when Gavin Hastings, Kenny Milne, Paul Burnell and Andy Reed faced up to New Zealand in Christchurch.
Sutherland, originally named on the bench, was promoted when Wyn Jones was ruled out with a shoulder injury sustained in training and the Hawick prop was quickly involved in the heat of the battle.
The scrums were being fiercely contested with the hosts possibly stung by Gatland’s claim earlier in the week that the Lions had “dented South Africa’s ego” at the set-piece. Criticising a Springboks scrum is akin to insulting his wife and this was a pack with a point to prove.
The backs looked up for it as well and an early hit by Lukhanyo Am on Elliot Daly was of the bone-crunching variety.
There were glimpses of Stuart Hogg and Duhan van der Merwe in the opening minutes but space was at a premium. Ali Price, the other Scot in the team, was at the heart of it all and played throughout with admirable calmness.
South Africa, as expected, were kicking for territory, hoping to pressurise the Lions into mistakes and it was working.
They drew first blood when Tom Curry was penalised for not moving away in the 13th minute. It looked tad harsh on the England openside but Pollard took full advantage and slotted over the penalty. He doubled the Boks’ advantage three minutes later and Curry was again the culprit, his late tackle on Faf de Klerk penalised by referee Nic Berry.
The Lions needed to gain a foothold and they were helped by a Biggar penalty halfway through the first half, which was immediately followed by a smart turnover from Maro Itoje, who was the outstanding Lion throughout.
But any hope that this signalled a momentum shift was quickly quashed as Pollard landed another two penalties to put the Boks 12-3 ahead.
Biggar squandered a chance to reduce the lead when he pulled a penalty attempt of his own and then handed Daly a chance to have a pop from the halfway line, but the centre’s long-range effort just fell short.
As the half-time hooter neared, the Lions finally found some space and Robbie Henshaw cut loose only to be stopped in his tracks by a textbook tackle from Willie le Roux.
South Africa changed their entire front row at half-time but it was the Lions who came out of the changing rooms with renewed ambition. Price quickly pinned the hosts back into their own 22 and when South Africa gave away a penalty, Alun Wyn Jones ordered a kick to the corner rather than a pop at goal. The Lions fancied their chances and the gamble paid off as the lineout driving maul was executed expertly, with Cowan-Dickie applying the finishing touch for the first try of the game. Biggar converted to reduce the Springboks’ lead to two points.
If the first half was cautious and tactical, the second period anything but.
Le Roux thought he had scored a try for the hosts but was adjudged to be in front of Am when the centre kicked down the left-wing channel. It was a tight call and the irony of television match official Marius Jonker disallowing the score would not have been lost on either coach.
Gatland had been livid about a South African being appointed TMO but he had cause to thank Jonker on this occasion.
He would have been less impressed with him a couple of minutes later when another Springboks try was referred upstairs. Makazole Mapimpi was the architect, aiming a delicate kick into the path of Pieter-Steph du Toit, but the flanker failed to gather. Mapimpi was first on the scene and wrestled Hogg for possession. The ball squirmed free but, crucially, was judged by Jonker to have gone backwards and de Klerk collected and touched down. Pollard missed the conversion attempt but the Boks were now 17-10 ahead.
If the Lions had been profligate in the first half in terms of the number of penalties they conceded, it was the hosts who were the guilty party after the break.
Biggar made them pay, kicking two quick penalties to reduce the deficit to a single point and the game was on a knife edge halfway through the second half.
South Africa continued to cough up penalties and a huge moment loomed for the Lions stand-off when he was handed an opportunity to kick from out on the touchline. Biggar held his nerve to put the Lions ahead for the first time in the match with 18 minutes left on the clock.
Hamish Watson, the fifth Scot in the squad, was off the bench by this point as both sides looked for reinforcements.
Pollard then showed he was fallible by missing a penalty attempt and you began to sense that this might be the Lions’ day. There was still time for a heart in mouth moment when the Lions made a mess of trying to play out of their own 22. South Africa thought they had scored a try but the TMO decided Cheslin Kolbe had knocked forward when he bounced the ball out of Liam Williams’ hands.
Owen Farrell, off the bench and switched to stand-off after Biggar went off for a head injury assessment, then increased the Lions lead with a late penalty.
Hogg had the final say, kicking the ball dead after the hooter to ensure victory for the Lions.