Durban: Australia opener Phillip Hughes became the youngest batsman in Test history to score a century in each innings on Sunday as his side prepared to set South Africa a huge total to win the second Test.
Australia ended the third day on 292-3, an overall lead of 506 runs, with two days left in the match.
Hughes, 20, whose test career started with a four-ball duck in the first test at the Wanderers, has since followed up with scores of 75, 115 and 136 not out.
He played a more sedate innings of 301 balls on Sunday, reaping 13 fours and hitting two sixes off spinner Paul Harris.
Hughes, whose twin-century feat eclipsed the record previously held by West Indies' George Headley, has banished thoughts that Australia would battle to find a replacement for the recently retired Matthew Hayden.
He has looked composed against one of the better attacks in the world throughout the match and has scored heavily on his favored off-side, particularly behind square
Hughes added 164 in 48.3 overs for the second wicket with captain Ricky Ponting (81), a partnership lasting more than two sessions which took the game away from the hosts.
Ponting also celebrated a notable batting achievement when he became the fourth highest run-scorer in test cricket.
Australia dismissed the Proteas in the first over of the day on their overnight score of 138, but despite leading by 214 runs did not enforce the follow-on.
When he had scored 61 in Australia's second innings, Ponting overtook compatriot Steve Waugh to claim the fourth spot on the all-time list with 10,928 runs in his 130th test.
Ahead of him are India's Sachin Tendulkar on 12,429 runs from 156 tests, the West Indies' Brian Lara on 11,953 runs from 131 Tests, and Australia's Allan Border on 11,174 runs from 156 tests.
The Australian batsmen did not seem troubled batting on Sunday, after the dramatic action Saturday when 13 wickets on both sides fell for just 129 runs.
There seemed to be less life in the pitch, and Ponting and Hughes were able to maintain a scoring rate of around four to the over during their partnership.
Ponting drove and pulled with precision, hitting 12 fours but going caught at deep square-leg for the second time in the game when he hooked Morne Morkel straight to Neil McKenzie.
Earlier Australia needed just three balls to end the South African first innings.
Fast bowler Peter Siddle claimed the remaining two Proteas wickets in the first over of the day.
Siddle induced an edge behind to keeper Brad Haddin from Dale Steyn (8) off the second ball of the morning, and then trapped Makhaya Ntini (0) in front next ball. The not out batsman was J.P. Duminy on 73.
Injured South African captain Graeme Smith, who suffered a fracture to his right little finger after being hit on the hand by Mitchell Johnson Saturday, did not come out to bat again.
Ponting did not enforce the follow-on, opting instead to increase his side's lead and ask the hosts to bat last on a pitch which has shown signs of deterioration.
Katich was the more aggressive of the two left-handed openers, hitting three fours and a six in his 30, but he was the only wicket to fall before the break, with the score on 55.
He pushed at a delivery from Jacques Kallis, playing with a right hand injury and stitches in his chin after being hit in the face Saturday, to be caught by Harris in the gully.
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