Australia found an unlikely batting hero in Scott Boland, but his gritty Test best was neutralised by a sensational spell by Wiaan Mulder, who helped pull off a dramatic win for South Africa in the rain-hit St George’s Park Test. Mulder nipped one into Boland, perfectly missing his defense to rattle his stumps, ending his 166-ball resistance. Australia's defiance, built piece by piece by Boland but anchored by Travis Head's century, was snatched away by it. The 37-year-old Boland had come in the previous evening to partner Head with Australia in a bit of strife, dead-batting 23 balls for two runs by stumps. But his duties as a nightwatch turned into a full-fledged responsibility on Day 5. The first session was consumed by rain, which had consumed much of the first two days. It delayed the second new ball for South Africa, who were also without the injured Anrich Nortje. The first phase was all about survival for Australia. Near-perfect deliveries from Kagiso Rabada whizzed past the outside edge and the off-stump. To entice an edge, Simon Harmer had a crowd surrounding Boland. Head ticked past that landmark, already on the verge of a century on the final day. His first in more than three years and only his second overseas Test century. Boland’s block-a-thon had some lively moments too. Against Rabada, and with a slip cordon, he pulled off an audacious ramp. Additionally, he extended his deliveries past the point with slaps and slices. But it was trumped by Mulder’s nagging accuracy, bowling with the keeper up, and seaming it off a pitch that also had the odd sharp turn for spinners. He first gave South Africa a break after the drinks when Head tried to climb the bounce but hit his stumps with it. With a second new ball shortly after, Mulder didn't abandon that ploy to relentlessly attack the stumps, perfectly complementing Rabada. Steve Smith, who dropped to No. 7 because of a neck problem, played a bizarre top edge while chasing Rabada's wide bouncer off the new cherry. It was caught by Matthew Breetzke, who made a small error. Temba Bavuma, in the distance, had his back turned, hoping it wasn’t a spill. After that, Boland and Alex Carey worked together to propel the visitors into the final session. But the magic touch from Mulder ended his valiant knock, the third-longest innings by an Australian nightwatch ever. Pat Cummins had played two vastly contrasting knocks in the first Test, but none of those runs mattered against a rampaging Mulder. The one to Boland had fallen in, and the one to Cummins had escaped the outside edge and struck the stump's top. Australia's hopes were rapidly fading as their number fell to eight. To add a little more drama, dark clouds started wafting in from one side. But there was no rain. Rabada stepped in quickly and floored Starc, who had been in a short stand with Carey up until that point, with a full ball. Marco Jansen completed the final act: a loose slash from Josh Hazlewood flew to the slips, giving Jansen his lone scalp of the innings and sparking victory celebrations. It was the first time since 1970 that South Africa had beaten Australia after enforcing a follow-on. Additionally, it only allowed them to win against Australia in the fourth innings.