Captain Michael Clarke welcomed an outstanding double century - and a promising 37-run lead - as Australia climbed to 487 for four on day four of the first Test at the Gabba in Brisbane.

Clarke and opener Ed Cowan put on 259 runs for the fourth wicket before the skipper and the veteran Michael Hussey added an unbroken 188 for the fifth to truly hurt South Africa's much-vaunted pace attack.

The right-handed Clarke's unbeaten 218 from 350 deliveries, 21 boundaries included, was not without flaw. A South African review ruled him not out in controversial fashion after television replays - and HotSpot - revealed a faint edge, which should have had caught him behind for 126.

Nine runs later, fast bowler Morne Morkel forced an edge to wicketkeeper AB de Villiers, only for umpire Asad Rauf to call a no-ball - the lanky right-armer's second costly foot fault of the match. Cowan, meanwhile, was dropped by fast bowler Dale Steyn at fine-leg on 123.

Steyn had the final say, eventually enjoying a piece of fortune in the wake of a solid straight drive from Clarke. The bowler got a finger to the ball, which in turn ricocheted in to the non-striker's stumps, with Cowan left stranded - and out for 136.

The left-hander's 257-ball vigil was laced with 17 boundaries and went a long way in answering critics calling for the return of all-rounder Shane Watson to the top of the order.

Monday's momentous effort was Clarke's third Test score of 200 or more. His form reminded all and sundry of the brilliance that took him all the way to 329 not out against India at the onset of this year. He later hinted at declaring in the first session of day five, attempting to force the result from a rain-hit, run-laden fixture.

Hussey made the most of the placid conditions and the tired attack, racing to 86 not out from a mere 109 deliveries, accruing a dozen boundaries as Morkel and company grew increasingly listless.

While debutant seamer Rory Kleinveldt managed to recover from his late expense at the hands of Cowan on Sunday, he still fetched an economy rate bordering on five - and probably won't crack the nod ahead of leg-spinner Imran Tahir come the second Test.

The Proteas even turned to the part-time spin of Graeme Smith, Hashim Amla and Alviro Petersen on Monday, in a bid to buy a breakthrough more than rest his frontline seamers.

This fixture isn't likely to bring a result, bar a miraculous collapse on Tuesday, but has afforded the battle for the number one Test ranking a wonderful precursor to the forthcoming deciders.