Sawt Falasteen - Australia claim three South Africa wickets as Sydney Test resumes

After rain again prevented play in the morning session, captain Pat Cummins declared his team's first innings at 475-4 after lunch to go after victory against the hapless Proteas.

Cummins's decision to declare deprived opener Usman Khawaja of the chance of completing his first Test double century, with the elegant opener stranded on 195 not out.

At tea on day four, South Africa were 71 for three with Temba Bavuma on 28 and Khaya Zondo not out five.

Skipper Dean Elgar had a big moment on six when Steve Smith flung himself to his right at second slip off Hazlewood to take a reflex catch but simultaneously grounded the ball.

After multiple replays from various angles, third umpire Richard Kettleborough gave Elgar not out but it was a very close call.

But Josh Hazlewood, bowling a lively opening spell, got Elgar with a brutal short-pitched delivery which clipped his glove for a catch by wicketkeeper Alex Carey.

Elgar's 15 follows in an underwhelming series of scores -- 3, 2, 26, 0.

"It's a pretty good wicket, taking a bit of spin and starting to break up with a little bit of (foot) traffic, but still good for batting," Hazlewood told the host broadcaster during a drinks break.

Offspinner Nathan Lyon was introduced into the bowling attack in the eighth over.

He stunned Sarel Elwee who did not play a shot and was bowled top of off-stump for 18 leaving the tourists 37-2 in the 18th over.

Four balls later Pat Cummins claimed the wicket of number three Heinrich Klaasen, caught off a lifter leg-side by Carey for two.

Australia have 59 overs to bowl on Saturday and potentially 98 more on Sunday's final day for a total of 157 overs to dismiss South Africa twice.

In the first Brisbane Test, the Proteas lost all 20 wickets in 86 overs and in Melbourne South Africa lasted 137.3 overs.

Australia are bidding for a series clean sweep over the closing two days to seal a place in the World Test Championship final in London in June.

Australia are 2-0 up in the series after winning the opening Test by a six-wicket rout in Brisbane inside two days, then hammering the Proteas by an innings and 182 runs in Melbourne.

I.Saadi--SF-PST