The All Blacks outscored South Africa five tries to one and saw off a powerful physical challenge, emerging the slicker of the two teams as they upset the odds.
“Oh, look, it's massive,” said Rennie of the result in the series dubbed ‘Rugby’s Greatest Rivalry’.
“We've got a leg up, although, obviously, it doesn't guarantee anything, and we know they are such a good side,” he said of the Springboks, who had been most pundits' favourites but were brought down to earth with a humbling bump.
“Next week's going to be just as tough,” added Rennie, who took over as All Blacks’ coach earlier this year and now has four successive wins under his belt after winning three matches in the Nations Championship last month.
“It's not about me,” he told the post-match press conference. “You know, I'm really pleased for the players. We've got a fantastic group of staff who work really hard, and it's a special night.
“It's tough to win at Ellis Park against a high quality side, but we're still in our infancy. We're still getting a heap around exactly how we want to play and grow and we've got some good young men coming through.”
Rennie said the turning point came in the 55th minute when South Africa had three successive scrums near the All Blacks posts, electing to try and bruise their way over instead of taking kickable penalties but failed to score.
New Zealand went down the other end and scored a try when Fabian Holland charged down a clearance, regaining the lead and never looking back.
“That was a bit of a soft one and then we were under the pump for a number of minutes, so to come out of that and then get a little bit of territory was massive,” the coach added.
“Somewhere in there, we were able to camp down in their half and we got rewarded for putting the Springboks under pressure.
“I thought we were better in the last 20 minutes, and they ended up getting a couple of (yellow) cards which made the job a little easier.”
The two sides meet in the second test in Cape Town on Saturday.
“I know the score might look convincing, but it was an absolute arm wrestle. We were under the pump but the boys showed up. We defended and defended and then we were clinical when we got our opportunities," Rennie added.
"A massive effort, a great result for us, but we're wary of the response that we'll get next week.”
The All Blacks are embarking upon their first full tour of South Africa since 1996! Marketed as the 'Greatest Rivalry' series, the winner will come out not only with the bragging rights but World Rugby's number one ranking. Keep up to date throughout August and September with news, previews and more.
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