Usman Khawaja made his highest Test score, while Steven Smith overtook Sir Donald Bradman in the record books with his 30th Test hundred, as Australia gained a stranglehold on the third Test against a hapless South Africa.

Khawaja was ruthless on a slow SCG surface to finish unbeaten on 195 and anchor Australia’s massive 475 for 4. But their push for a declaration before stumps on day two was thwarted by rain ending play an hour early.

With a declaration looming, Khawaja and Travis Head accelerated after tea with Australia keen on moving the match forward due to more rain forecast in Sydney on days three and four.

In what has become a trademark, Head played a swashbuckling innings to smash a flagging South Africa attack with a 59-ball 70 before holing out. In his first Test match since 2018, and having tested positive for Covid-19 on a rapid antigen test before play on day one, Matt Renshaw was on 5 not out.

Khawaja bettered his highest Test score of 174 in streaky fashion with a gloved boundary that just beat high-flying wicketkeeper Kyle Verreynne. His 13th Test century took him level with Wally Hammond, Doug Walters and VVS Laxman as the only batters to have struck three consecutive tons at the SCG.

Having revived his Test career a year ago with twin centuries against England on this ground, Khawaja has now hit four centuries from seven Tests at the SCG with an average over 100.

It ended a frustrating Test summer for Khawaja, who had missed out on Australia’s run glut and only averaged 27.43 from seven previous innings.

Khawaja combined in a 209-run partnership with Smith to torment South Africa for most of the first two sessions on day two. It was their 10th century partnership from just 33 innings and their highest stand, overtaking their 188 against England at the SCG in 2018.

Having moved past Bradman on the career Test century list with his 30th ton, Smith fell for 104 after tamely spooning a return catch to spinner Keshav Maharaj.

After a slow start, Smith produced a masterclass and reached his ton with a pull shot to the boundary off Anrich Nortje. His back-foot trigger movement was more pronounced in this innings, having been refined earlier in the season, but it didn’t affect his game with Smith toying with the bowlers.

It would have particularly satisfied Smith, who in 20 previous innings against South Africa averaged 41.67 – nearly 20 below his career mark. His only Test ton was in his first innings against them when he struck 100 in Centurion in 2014.

In the process, Smith overtook Matthew Hayden and Michael Clarke to sit fourth overall in Test career runs for Australia. He also passed 1000 Test runs at the SCG as he struck his fourth ton on his home ground.

Another strong Australian batting effort put them on track for a clean sweep of the series with victory to secure a position in the World Test Championship final in June. They also completely sucked the life out of a beleaguered South Africa, who have been out of answers.

With just four wickets in 131 overs, the spotlight might further shine on under-pressure skipper Dean Elgar who has seemingly been reactionary and conservative with his tactics.

He juggled his bowlers sometimes bafflingly like when Nortje and spearhead Kagiso Rabada were not used after lunch with offspinner Simon Harmer taking an almost brand new ball.

Harmer had been under-bowled on day one and in the first session, but struggled to make an impact and was hit for a huge six by a fleet-footed Smith.

Nortje couldn’t quite summon the same fire he conjured during his heroic day one effort, where he claimed the only two wickets, while Rabada was wayward to continue a disappointing series.

There was relief for left-arm spinner Maharaj after removing Smith out of nowhere. He was finally rewarded having leaked 247 runs off 75.5 overs in the series before his long overdue first scalp.

Their chances of a victory to revive their slim chances of making the World Test Championship final appear forlorn. To avoid a series whitewash, South Africa might need Sydney’s temperamental weather to further intervene.