Big centuries from Hashim Amla and AB de Villiers on day three of the fourth and final Test between South Africa and Australia in Perth set the home side an unlikely victory target of 632.
Amla made 196 and de Villiers 169 as South Africa were bowled out for 569 in their second innings and Australia closed the day on 40 without loss.
The world record successful run chase in a first-class match is 541 although many times have hit 450 and above to save matches but with two full days remaining, the task ahead of Australia is a huge one.
They would need contributions such as Amla's and de Villiers', as the pair put on 149 for the fourth wicket after Jacques Kallis had been dismissed for 37.
Amla hit 196 in 221 balls with 21 fours having swiftly moved on from 99 not out to make an 87-ball century. De Villiers hit 169 in 184 deliveries including 21 fours and three sixes.
Only two bowlers were taking wickets for Australia, left-armers Mitchell Starc (6-154) and Mitchell Johnson (4-110).
Johnson trapped Dean Elgar in front as he registered a pair on debut and they finally dismissed Francois du Plessis for a low score when he was caught by Michael Clarke off Johnson for 27.
Vernon Philander was unbeaten on 14, Robin Peterson and Morne Morkel fell for a ducks and Dale Steyn made eight as South Africa built their huge lead.
Australia used eight bowlers in their futile attempts to limit the flow of runs - South Africa scoring at more than five runs per over - and take wickets, including Ricky Ponting, who is retiring from international cricket after this match.
He will have a role to play as the match progresses but openers David Warner (25 not out) and Ed Cowan (12 not out) saw to it that Shane Watson, Ponting and the rest didn't have to bat today.
© Cricket World 2012
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