However, Ponting and Clarke's partnership of 113 steadied things. Then debutant Marcus North's composed 47 not out, and wicketkeeper Brad Haddin, unbeaten on 37, added 72 for the sixth wicket before bad light, followed by rain, ended play early.

Ponting, who scored 101 and 99 in Melbourne and 0 and 53 in Sydney during the recent series in Australia, crunched 83, with 11 fours and a six, before he was dismissed by Makhaya Ntini [Images] after leaving a delivery that moved in, hit the top of his pad and went on to the stumps.

The Australian captain had earlier been dropped by opposite number Graeme Smith [Images] at first slip off Steyn on 40, and promptly hooked the next ball for six.

He also won a decision reviewed to the third umpire on 70 after the South Africans disagreed with umpire Billy Bowden's not out verdict for a caught behind appeal off Morkel.

Clarke also went before tea for 68, which included 10 fours, after a wide, full delivery from Steyn kept swinging away and wicketkeeper Mark Boucher [Images] gratefully accepted the catch.

Fast bowler Steyn finished the day with three for 82.

A fine new-ball spell by Steyn and a magnificent catch by Neil McKenzie [Images] in the morning had rocked Australia, who won the toss and chose to bat.

Debutant Phillip Hughes fell in the first over for a duck, edging an awful cut at a Steyn bouncer into the gloves of Boucher.

Fellow opener Simon Katich [Images] (3) survived some scares outside off stump before McKenzie terminated his 40-minute innings with a superb one-handed catch in the gully, diving full length to intercept a back foot drive off Steyn.

South Africa made another telling breakthrough 45 minutes before lunch when Morkel had Michael Hussey [Images] caught at second slip by Jacques Kallis [Images] for four.