Pienaar said a victory Saturday would be a big confidence-booster for the Springboks in their second season under coach Heyneke Meyer.
"I know the record isn't great but that's the exciting thing now for this group now," he said. "If you want to grow as a group and go forward you would like to get a result here."
"We are a fairly young squad ... so this would be a massive step in the right direction."
South Africa's record at home against the Wallabies is near-perfect the team has lost only once to Australia.
The Wallabies broke a 47-year drought with Kurtley Beale's late penalty goal at Bloemfontein in September 2010 giving the visitors a 41-39 win.
"At home on the Highveld, it is more of a continuity game and you get that continuity," Meyer said. "Away from home it is more of a contesting game where you get the teams contesting every single lineout, so we have to be disciplined."
South Africa's chances improved with news Thursday that Australia captain James Horwill has been ruled out of the match.
The Australian Rugby Union said Horwill strained a hamstring in a training run on Tuesday. Kane Douglas will replace him in the second row and scrumhalf Will Genia will take over the captaincy.