Proteas set huge target

Pretoria - Australia declared its second innings on 290-4 early on the fourth day of the first Test against South Africa for a mammoth lead of 481 on Saturday.

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Mitchell Johnson then removed both South African openers in his first two overs to have South Africa 12-2 and on the ropes against the near-unplayable form of the ferocious Australia fast bowler.

Johnson forced Alviro Petersen (1) out to an edge behind to wicketkeeper Brad Haddin in the second over and removed South Africa captain Graeme Smith for 4 to a sharp catch by Alex Doolan at short leg in the fourth over of the innings, continuing the speed and aggression he used to destroy South Africa in the first innings.

Australia was racing toward a crushing victory over the top-ranked Test team.

At the start of the day, Australia skipper Michael Clarke, who was batting at the time, called a halt to the Aussie second innings at SuperSport Park as soon as Shaun Marsh fell to Dale Steyn for 44 in the third over of the day, setting South Africa an unlikely victory target of 482 that was made much more unlikely with Johnson's red-hot form.

David Warner made 115 and Doolan 89 on Friday to anchor Australia's second innings, leaving South Africa needing a world-record chase to win and six sessions to survive the threat of Aussie quick Johnson, who took 7-68 in the first innings.

The highest successful fourth-innings total in a Test at Centurion is 251.

And after Johnson's two immediate strikes, Australia was in a near-unstoppable position to win the series-opener and become the first team to beat South Africa in a Test at Centurion in 14 years.