SYDNEY - South Africa's pursuit for the top spot in the Test rankings started on a bright note after their bowlers left Australia at 267-6 at stumps on day one of the third Test at the Sydney Cricket Ground. Michael Clarke waged a lone battle with a battling 73 not out with Mitchell Johnson keeping him company on 17 after captain Ricky Ponting won the toss and elected to bat. South Africa's bowlers inflicted more misery on the Australian batsmen following their exploits in the first two Tests. Dale Steyn claimed 2-71 while the rest of the bowlers shared a wicket each. Australia were reeling at 162-5 before Clarke and wicketkeeper-batsman Brad Haddin resurrected their innings with a 75-run partnership for the sixth wicket. But Steyn accounted for Haddin for 38 just before stumps with the second new ball. Australia got off to a strong start but openers Simon Katich and Matthew Hayden having had a role reversal. Katich raced to 47 from just 52 balls before Jacques Kallis had him caught by AB de Villiers, while Hayden was the more sedate partner, determined to hold on to his Test spot. Hayden survived the first session and was unbeaten on 31 along with Michael Hussey after Morne Morkel removed captain Ricky Ponting for a first-ball duck. Hayden, beginning to look settled went for an expansive drive but cost him his wicket to Dale Steyn for 31 before spinner Paul Harris saw the back of Mike Hussey. Australia's slide continued as debutant batsman Andrew McDonald was sent back by Makhaya Ntini for a nervous 15 after being stuck on the helmet by Morne Morkel initially. Australia, blighted by injuries to key players, handed Test debuts to middle order batsman Andrew McDonald and left-arm pacer Doug Bollinger, while South Africa went unchanged into the game. South Africa have already sealed the series after winning the first and second Tests in Perth and Melbourne. SCOREBOARD AUSTRALIA 1st innings ML Hayden b Steyn 31 SM Katich c de Villiers b Kallis 47 RT Ponting c Boucher b Morkel 0 MEK Hussey c Kallis b Harris 30 MJ Clarke not out 73 AB McDonald c Boucher b Ntini 15 BJ Haddin b Steyn 38 MG Johnson not out 17 EXTRAS (lb 7, w 2, nb 7) 16 TOTAL (6 wickets; 88 overs) 267 To bat NM Hauritz, PM Siddle, DE Bollinger Fall of wickets: 1-62 (Katich, 12.6 ov), 2-63 (Ponting, 13.5 ov), 3-109 (Hayden, 33.3 ov), 4-130 (Hussey, 40.6 ov), 5-162 (McDonald, 56.4 ov), 6-237 (Haddin, 81.4 ov) BOWLING DW Steyn 21-4-71-2 M Ntini 19-5-53-1 (2nb, 1w) M Morkel 17-3-49-1 (5nb) JH Kallis 15-4-43-1 (1w) PL Harris 16-3-44-1 South Africa team: ND McKenzie, captainGC Smith, HM Amla, JH Kallis, AB de Villiers, JP Duminy, wicketkeeperMV Boucher, M Morkel, D Steyn, P Harris, M Ntini Toss: Australia, who chose to bat first Test debuts: DE Bollinger and AB McDonald (Australia) Umpires: BF Bowden (New Zealand) and EAR de Silva (Sri Lanka) TV umpire: RJ Tucker Match referee: RS Madugalle (Sri Lanka) Reserve umpire: GA Abood.