South African off-spinner Simon Harmer has said the Proteas came to a crucial realisation during the second Test in Gqeberha: Australia's batters are human and can be put under sustained pressure.

Harmer's contribution with the bat was central to South Africa's recovery. His 82 and record eighth-wicket partnership of 183 with Temba Bavuma carried the hosts to a match-winning total of 425 for 9 declared. Bavuma's career-best 179 helped South Africa take command of the rain-shortened game.

"To to be 1-0 down and to be able to turn it around and then to be 40 for 4 and be able to turn that pressure and put it on them and then to realise that actually, they are human and if we bowl well and put them under pressure, there is the possibility that we can get on top of them, was really nice to see. Durban was a tough few days for us with our backs against the wall and there was nowhere to go. It was nice for us to turn it around and to be able to put them under pressure," Harmer said, as quoted by Cricinfo.

They took 20 wickets in 149 overs in Gqeberha, a sharp improvement on the 16 wickets they managed across 195 overs in Durban. The return of Kagiso Rabada, who has a fantastic record against the Aussies, was the most obvious difference. Although Anrich Nortje left the field with an apparent groin problem in his fourth over, Wiaan Mulder stepped into the third seamer role and bowled with both skill and assurance to help complete a South African fightback.

"There was a lot of motivation and fire burning in the belly of a lot of the boys that we didn't put our best foot forward and that we didn't lose on our terms in Durban. The character that Marco showed in that first innings, both with bat and ball, and KG today and Wiaan everybody stepped up. When the team really needed somebody to break it open, they were able to do that. We'll take a lot from this win and a really good feeling to go into Cape Town 1-1," Harmer said

What went wrong in Durban and how did South Africa correct it?

South Africa's first-Test defeat at Kingsmead was largely self-inflicted. Almost every batter in the line-up was guilty of poor shot selection in the first innings, and the team acknowledged it openly. The bowling effort in Durban was equally frustrating. South Africa erred in selection by fielding two spinners on a surface that offered less turn than anticipated, and they were unable to exploit the vulnerabilities in Australia's batting order.

"If you look at the dismissals, it was quite evident there weren't a lot of good balls that got us out but we managed to find ways to get out. The most frustrating thing in Durban was knowing that there were a couple of guys that had come either back into the Test team or out of position, and we weren't able to exploit that," Harmer said.

In Gqeberha, Harmer played as the specialist spinner ahead of Keshav Maharaj, and the team corrected both their batting and bowling errors. Across the two Tests, Harmer bowled 97.5 overs, more than any other bowler on either side, returning figures of 4 for 291. By his own admission, those numbers fell short of what he had hoped for.

"I'm not one for excuses, so I'll take it on the chin. I believe that I could have bowled better. In both Tests, it's been more seamer-friendly than it has been spinner-friendly but I'll definitely sit back and find ways that I could have done more," he said.

With Nortje unlikely to be fit for Cape Town, South Africa may also consider either Corbin Bosch or Gerald Coetzee as a like-for-like pace replacement. Newlands is a venue where teams rarely go without a spinner, though no Test has previously been played there in October, which adds further uncertainty to selection planning.

How does Harmer view this South Africa side compared to earlier generations?

Harmer has been part of the South Africa set-up for the past year after coach Shukri Conrad sought him out for away tours to the subcontinent. He was South Africa's leading wicket-taker in both Pakistan and India, and he played a key role in their comeback from defeat in Lahore to victory in Rawalpindi, as well as in their historic win over India at home for the first time in 25 years. The Gqeberha win marks his involvement in a third consecutive South African comeback from a difficult position. Harmer believes the squad is ready for the challenge that Cape Town presents.

"Regardless of what's thrown at us, we're able to adapt and overcome. I'm really looking forward to what Cape Town throws at us. Test cricket is about simplistic basics and doing the good things well," he said. "There's still a lot of cricket to be played. We'll take the positives from this, and make sure we learn from our mistakes over the last two games, and put our best foot forward," Harmer said.