A burst of wickets from Andre Nel, who finished the day with figures of 4 for 58, towards the close helped South Africa counter an aggressive century from Ricky Ponting, who had given Australia the early momentum with solid support from a belligerent Matthew Hayden.
By the end of the day though, Australia were perilously placed at 8 for 239 after having chosen to bat, and South Africa will rightfully feel that they made the most of a good situation.
Ponting's decision to bat first on a tricky pitch - damp spots delayed the start by 30 minutes - could come in for some criticism.
The day began badly for Australia as Phil Jaques, the debutant, was sent on his way with two runs on the board as he inside-edged Shaun Pollock to short leg via thigh pad. The South Africans missed a trick or two, bowling the wrong line and length to Ponting when he first came in, then spilled a simple chance, and paid the price for it.
Ponting was keen to stamp his authority on the game early, and took a few chances. Off just the third ball he faced, he flashed straight to where third slip would have been, but was let off as the slips cordon was split.
Then, on 17, he mis-hit a pull off Jacques Kallis straight to Nel at midwicket only to see the chance go straight into the fielder's hands and out.
Soon after he was let off, Ponting stroked three boundaries, one pull in front of square and two hook shots placed beautifully over square leg, and the momentum was with him. South Africa's bowlers, perhaps a touch too excited at bowling on a pitch that provided some seam movement and a bit of uneven bounce thanks to the damp spots, failed to consistently pose questions to the batsmen.
Hayden sensed that this was not a pitch to bash the ball from the word go, and knuckled down to keep the bowling out. Graeme Smith packed the cover region, tempting Hayden to drive the quick bowlers over the top, but he resisted, choosing instead to defend watchfully till the bowlers landed the ball where he could hit it. And eventually they did, providing width, and he took full toll, carving the ball through cover-point by opening the face of the bat just a touch.