Australia left South Africa reeling on 175 for 7 at tea on day one of the first Test on Thursday as Mitchell Starc made a successful return from a gruesome leg injury.
After winning the toss and electing to bat in Perth, the visitors lost four early wickets to the Australian pace attack as they slumped to 32 for 4.
South Africa fought back through Temba Bavuma and Quinton de Kock, but Bavuma and Vernon Philander fell just before tea as Australia regained control.
De Kock was unbeaten on 53 after surviving a review on 47 when Australia unsuccessfully challenged for a caught-behind decision.
Bavuma made a composed 51 but he fell to a brilliant catch by Shaun Marsh — whose brother Mitchell had also taken a screamer to dismiss opener, Stephen Cook.
The South African number six was superbly caught down low by Shaun Marsh at short leg from the bowling of Nathan Lyon to end a valuable 71 run sixth-wicket stand.
Philander (10) fell to the last ball before tea, dragging an attempted pull shot back onto his stumps to give Starc his third wicket.
Starc, returning to action after suffering deep cuts when he collided with equipment in training, was the pick of the bowlers with 3-42.
The day also started with an outstanding Marsh catch, with Shaun’s younger brother Mitchell leaping high at gully to remove opener Stephen Cook for a duck after Starc had bowled the first four balls of the match.
The South Africans were soon in worse trouble, with Hashim Amla also falling without a score.
Amla pushed at a Josh Hazlewood delivery and provided a simple catch for Australian skipper Steve Smith at second slip.
A tough chance from Dean Elgar was grassed on 10, but he made just two more before being caught behind by Peter Nevill from the bowling of Hazlewood (2-47) with the score on just 20.
JP Duminy never looked comfortable and also benefited from a life when he was on 8, but like Elgar, he could not capitalise and was caught behind for 11 off Peter Siddle.
Duminy called for a review and it took quite some time before umpire Nigel Llong’s decision was upheld by the third umpire Richard Kettleborough.
South Africa, who beat Australia 5-0 in their recent one-day series, left out paceman Morne Morkel and promoted spinner Keshav Maharaj to make his Test debut.