The Springboks' current problems are down to a lack of confidence says Sky Sports pundit Thinus Delport.
The Boks overturned a 16-point half-time difference to beat Ireland 32-26 in Johannesburg last week, but were downed 26-20 in Cape Town the week before - South Africa's first loss to Ireland on home soil in their history.
Both games were blighted by basic handling errors from the hosts, and they were largely unable to breach the Irish defence in the First Test despite playing for almost an hour with an extra player.
Delport says the second half of the Ellis Park Test was a much better showing, but the overall performance of the Boks still needs to improve.
"It was a really good forty minutes of rugby, but there were also a lot of mistakes," said Delport. "The fact that they struggled in their exit strategy three times out of four restarts in the second half really put them under pressure.
"So despite the win there was plenty for them to work on this week.
"You've really got to be switched on when receiving the restarts, and the Boks appeared to not be concentrating hard enough in those moments.
"Whether it's the pressure of the game situation or losing the previous week, it's not something they can afford in Port Elizabeth."
South Africa produced a flurry of handling errors in each of the first two games against Joe Schmidt's side, which almost cost them the series.
The Cape Town Test was the first in charge of the Springboks for former Stormers coach Allister Coetzee, and Delport believes it is the adaptation to the new structures that has thrown the Boks off their game.
"Sometimes when a new coach comes in there is such a focus on game-plans that players end up focusing more on that rather than on the basics of their game, which is what it looked like at Newlands and Ellis Park.
"It seemed like the confidence that comes with playing together is not quite there. In the second half in Johannesburg that confidence grew a bit and you could see it in the way plays were executed.
"If that confidence grows even more, then we should see a far tighter Springbok outfit this weekend."
The pundit picked out two Lions players as the injection that helped that Boks overturn the lead built up by the Irish. Winger Ruan Combrinck and No 8 Warren Whiteley were introduced at half-time at the expense of Lwazi Mvovo and Duane Vermuelen, and their impact was felt by visitors as the pair each dotted down for a try.
Their form has been rewarded with starts this weekend, with Mvovo dropped to the bench and Vermuelen out injured, and Delport has backed their selection.
"I think as players they looked confident in their decisions in Johannesburg. Other guys were a bit more hesitant but Whiteley and Combrinck backed themselves and played with conviction.
"They added that spark, in the same way that Pieter-Stef du Toit did in the first Test, and it lifts the other players.
"The questions now is whether they are able to do that from the outset of the game."
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