AUSTRALIA v SOUTH AFRICA, SECOND DAY TEST, DAY THREE SCORE: South Africa 189 and 1-15, Australia 8 (dec)-575 and lead by 371. SUMMARY: After Tuesday's scorcher, Melbourne stayed true to its fickle form and the rain arrived. After a late start to play, the home side set about building a monster lead given allrounder Cameron Green is out of the attack with a finger fracture and Mitch Starc also is labouring with a finger injury. David Warner returned and Anrich Nortje bowled him first ball in a rare highlight for the tourists. After losing Travis Head and Warner to Nortje in successive deliveries, Australia steadied and Alex Carey's first Test century (111) cemented their impregnable position. Green and Head also made 51 apiece. South African captain Dean Elgar was out to a third-ball duck before the rain mercifully returned for his team, ending the day's play early. The forecast is for no rain on Thursday, which is when Australia should win the Test and the series. MAN OF THE MOMENT: Carey has done little wrong since just over a year ago, when Tim Paine dramatically resigned as captain and handed over the wicketkeeping gloves. Apart from his maiden ton, he took a fine diving catch to dismiss Elgar. KEY MOMENT: For South Africa to have any chance of challenging Australia, they needed a steady start. Elgar's duck continues their wretched batting form, with the tourists not making it past 200 in their last seven Test innings. STAT OF THE DAY: Australia posted their fifth-highest Test total at the MCG. QUOTE OF THE DAY: "We've got a lot of work to do here, we've got a few in the casualty ward and that's going to limit our ability to press the whole time in the second innings." Australian coach Andrew McDonald. Australian Associated Press