South Africa captain Dean Elgar felt vindicated after his "bold" decision to bat first paved the way for a dominant second test win over New Zealand that levelled the series on Tuesday.

The Proteas' batsmen had been routed for 95 and 111 in the series-opener at Christchurch on the way to their second-worst test defeat after being sent in to bat first by New Zealand's stand-in skipper Tom Latham.

Despite a green-tinged wicket and New Zealand's unbeaten record at Hagley Oval when fielding first, Elgar backed his batsmen to turn things around in the Christchurch rematch.

Against one of the world's top seam attacks, they repaid their captain's faith with 364 in the first innings and pressed the advantage with 354 for nine declared in the second to set up a dominant 198-run victory on day five.

"Bold decision and one we had to take as a unit, luckily it paid off for us," said opening batsman Elgar.

"It might have backfired on us and I would've looked like an absolute idiot. I am one of those guys who live for the decisions that I make for the side."

South Africa leave New Zealand with their proud record of never losing a test series to the Black Caps intact, a run that dates back to 1931/32.

The Proteas have again proved their fortitude under pressure, having come back from a 1-0 deficit to overhaul India 2-1 in the home series in December-January.

A 10-day Covid-19 quarantine upon arrival in New Zealand and injuries to key players added to the challenges, but South Africa found inspiration in unlikely places.

Playing his second test, 32-year-old opener Sarel Erwee scored 108 in the first innings of the second test, while rookie wicketkeeper Kyle Verreynne produced a brilliant, unbeaten 136 in the second innings to all but bat New Zealand out of the game.

"We have got a young exciting group, there's no lack of talent in the group," said Elgar.

"We just got to stick with what we have, work with what we have at the moment.

"We will get there, but it will take time."