Perth - Hashim Amla scored a sparkling century to drive South Africa to an almost unassailable lead of 382 runs at lunch on the third day of the third and final Test against Australia on Sunday.

Picking up where he left off on Saturday, where he helped the tourists plunder 206 runs in the extended third session, Amla reached 149 not out with his team 320 for three at the break.

Jacques Kallis was the one batsman to fall, leaving AB de Villiers (18) to support Amla as the Australian bowlers failed to get the breakthroughs they desperately needed to keep alive their slender hopes of winning the match and the series.

After the first two Tests in Brisbane and Adelaide ended in draws, South Africa only needed a third in Ricky Ponting's last Test to ensure they remained the world's number one side.

They will now expect to do better than that and win consecutive series in Australia after their maiden triumph in 2008.

Amla resumed on 99 with his team 230-2 on a bright, sunny morning at the WACA and he reached his 18th Test century with a single to long leg from the third delivery of the day - the 87th he had faced.

Peppering his innings with some sublime cover drives for a good few of his 17 boundaries, Amla's comfort at the crease was an uncomfortable reminder for the Australians of his unbeaten 311 against England at the Oval in July.

Of the very few chances, the best was probably when an ugly slice just cleared the finger-tips of Mike Hussey at gully.

Australia's pace unit, acclaimed after ending South Africa's first innings for 225, toiled in the Perth sunshine but their best efforts mostly served only to slow the flow of runs.

Starc, who had figures of 2 for 103, removed Kallis for 37 with a bouncer when the all rounder top edged a hook shot to Mitchell Johnson at fine leg.

The 418 scored by West Indies against Australia in 2003 was the highest successful fourth innings run chase in Test cricket, while South Africa chased 414 to win the corresponding Test at the WACA four years ago. - Reuters