If his team had converted all their chances they could have given the Wallabies a "good hiding" in Port Elizabeth, frustrated Springbok coach Rassie Erasmus said.
Though happy with the 23-12 win in front of 41,300 fans in Nelson Mandela Bay Stadium, he wants his men to be much sharper when they face the All Blacks on Saturday.
While the Boks scored tries through Aphiwe Dyantyi and Faf de Klerk, Erasmus says SA cannot afford to leave points out on the field against New Zealand in Pretoria.
"A positive from the Port Elizabeth Test was that even though we did not score a lot of tries we created a hell of a lot of opportunities," Erasmus said.
"I thought that if we had scored those extra tries we could have given them a good hiding. But in the end it was a close game because Australia played territory well in the second half.
"Though I was disappointed we left points out there, I am happy for the win. The frustration is not about the result. I guess the moment we start talking about leaving points out there, we are taking the win for granted and we are going down the wrong route.
"We must first be happy about the win, but we did leave a lot of points out there. We will now work on converting those into actual scores.
"But at least the opportunities were created, which we struggled to do earlier in the year."
It was a defeat that piled more misery on Australia, who are bottom of the table with just a single win after five rounds.
The victory enabled SA to stretch their unbeaten run at Nelson Mandela Bay Stadium to six matches.
Ahead of the clash, Erasmus warned that his men would have to maintain their intensity if they wanted to get over the line.
The Boks have blown hot and cold this season, but consecutive wins over New Zealand and Australia are good omens.
The Bok coach said he is happy that his team is winning, even after changing the squad.
"In the past couple of months when we made changes we lost matches. Now we are starting to win games when we make changes, and that is a positive.
"We did not play tactically well against Australia. But the guts and character the boys showed in the second half in Port Elizabeth was great.
"The Boks are trying to grow and each week trying to get better. So there has been growth this season, and that was our ultimate goal."
Australia enjoyed their best spell of the match after halftime, and the Boks were forced to build a brick-wall defence to hold them at bay after Dyantyi was yellow-carded.
Asked why he had not given replacements Elton Jantjies and Damian Willemse a run, Erasmus said: "We make changes in the game as we see fit, like in the All Blacks game we substituted our captain, Siya Kolisi, with 10 minutes to go in the Test match because he was tired. The Boks only make tactical changes when it will really change the game," he said.
New Zealand’s 35-17 win over Argentina on Saturday sealed not only a third consecutive Rugby Championship — and a sixth in seven years — but also gave the world another ominous reminder of their strength in depth a year from the next World Cup.
The world champions were missing several regulars in Buenos Aires, particularly in the pack, with Joe Moody, Owen Franks and captain Kieran Read among those absent, and Luke Whitelock replaced by Ardie Savea shortly before kickoff after taking ill.