The home side went down 8-24 at the all-new Allianz Stadium, conceding four tries while the Wallabies had to wait until the 79th minute to cross the chalk.
The loss came just a week after Australia won at Adelaide Oval, 25-17. However, poor discipline from earlier in The Rugby Championship came back to haunt them in Sydney.
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“We just struggled to get into the contest, didn’t we? They were very good post-tackle. They won the majority of the collisions with and without the ball,” Rennie said.
“Yeah, it was a frustrating day. We got to a stage where we needed to play more.
“We got sucked into kicking the ball back to them or kicking the ball out and giving them a set piece to play off.
“I just felt we needed to play with a little bit more tempo and really take the game to them.”
Rennie lamented an early yellow card and a string of penalties that set the tone of the match.
After the Springboks opened the scoring with the first try of the match, Matt Philip was sin-binned for one too many indiscretions in the build-up.
“Even from our structure, beyond that, we lost Matt Phillip early so you’re one short at the clean-out,” Rennie explained.
“They did a really good job early on stealing pills. We’ve got to be better. We gave away penalties early and it hurt us.
“The penalty count evened up in the end, but even that last stanza – 15 on 13 – we had a five on one and we shelved it. Probably summed up our day.
“We allowed them to get all the momentum and play all the footy down our end.
“We’re really disappointed in our ability to build phases,” he added.
“The quality of our carry, the urgency of our cleans has got to be better. It’s a massive part of our game. We were good last week and not good enough tonight.”
Each team in the competition has two wins and two losses with two rounds remaining in The Rugby Championship.
Asked whether it was a case of two steps forward, one step back, Rennie said the results paint a picture of just how competitive the sport is.
“It just highlights how tough international footy is at the moment,” he said.
“The teams are so even. You’re five per cent off, you get hurt – we saw with Argentina and the All Blacks as well.
“Our job is to make sure we can get that sort of stuff going against the All Blacks in a couple of weeks.”
Australia faces New Zealand on Thursday, September 15 for the first Bledisloe Cup match at Marvel Stadium in Melbourne.
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