Smith joins Khawaja with century, Australia 394-4

SYDNEY :Steve Smith celebrated his 30th century and Usman Khawaja moved past 150 to push Australia to 394 for four at tea, as South Africa's hopes of a face-saving win faded on a placid day-two wicket during the third test in Sydney on Thursday.

Smith joined a group of 14 cricketers with his 30th test ton late in the session before spinner Keshav Maharaj had the number four caught and bowled for 104, ending a 209-run partnership with opener Khawaja at the Sydney Cricket Ground.

Reprieved on 119 when Anrich Nortje missed a catch, Khawaja rolled on and was 172 not out at the break, with Travis Head on 17.

The match is a dead rubber after Australia sealed the series with wins in Melbourne and Brisbane, but Pat Cummins's side can book their place in the World Test Championship final with another victory.

South Africa hope to salvage some pride from the match but Smith was their only wicket - and Maharaj's first for the series - after Australia resumed on 147 for two in the morning.

Pakistan-born Khawaja collected his 13th test ton to continue his love affair with the SCG, which is just down the road from the two-bed flat he grew up in.

The 36-year-old Queensland captain reignited his international career in last year's New Year's test at the venue, scoring twin Ashes hundreds against England.

Nearly an hour into the second session, Khawaja cut Rabada straight to point where a startled Nortje misjudged the flight of the ball.

It brushed past his leg on the way to the fence, leaving Rabada fuming.

Khawaja struck three fours off Rabada in the next over, with two edges racing between the lone slip and gully.

Teaming up with Smith to attack Maharaj, Khawaja drove a half-volley off the spinner through the covers to bring up his 150 on the