Michael Clarke scored an unbeaten double century as bat dominated ball on day four of the first Test between Australia and South Africa in Brisbane.
Resuming on a potentially parlous 111-3 in reply to the tourists' 450, Aussie skipper Clarke (218 not out) and Ed Cowan (136) put on 259 for the fourth wicket to put the hosts in a good position.
Cowan's run out in the 85th over brought Michael Hussey to the wicket and he batted through to the close, ending on 86 not out to leave the South Africa attack in tatters.
From a position of superiority the Proteas now find themselves chasing the game heading into the final day, behind by 37 and with quick runs in the morning could face an anxious session and a half at the crease.
Cowan and Clarke added 103 before lunch without a single scare, the former passing a hundred for the first time in Tests off 185 balls.
Progress had slowed before the interval but Cowan pulled Vernon Philander for four in the second over after the resumption and that briefly seemed to free both batsmen, Clarke taking three fours off the next Morne Morkel over to move into the 90s.
A single brought up the 200 stand before Clarke reached his own ton in similar fashion, but after Cowan was dropped in the deep on 123 Dale Steyn, involved in a mix-up with Jacques Rudolph on that occasion, made amends by running out Cowan when he got a finger to the ball with the batsman backing up.
It turned out to be the only success of the day for the beleaguered South Africans on an even-paced Gabba pitch that suited Clarke down to the ground.
His third fifty took 70 deliveries and his fourth just 55 as Graeme Smith, without a spinner following the injury to JP Duminy, bowled himself, Hashim Amla and Alviro Petersen in a bid to spare his frontline attack.
Clarke did have one life, when an inside edge off Morkel was called a no-ball, but his concentration was unwavering as he passed 200 for the third time in 2012.
Hussey also capitalised, reaching fifty in 68 balls with six fours as he and Clarke added 188 for the fifth wicket.