South Africa thrashed Australia by 309 runs in the third and final Cricket Test at Perth on Monday. On the fourth day, chasing victory target of 632 runs for a win, the hosts were all out for 322 in their second innings. The Proteas sealed the three-Test series by a One-Nil margin. The first two Tests were drawn. By winning the series, South Africa held on to their Number One Ranking in Test Cricket. Graeme Smith's South Africans became the first team in two decades to defeat Australia on home soil in consecutive tours. The West Indies were the previous team to achieve it in 1992-93.The Perth match was also South Africa's 200th Test since being allowed back into international cricket. The final Scores:South Africa – 225 & 569Australia – 163 and 322.