Lunch Australia 475 for 4 (Khawaja 195*, Smith 104, Nortje 2-55) vs South Africa

Rain might have thwarted Usman Khawaja's bid for a maiden Test double-century after the first session of day three was washed out at the SCG. Khawaja remains stuck on his highest Test score of 195, while Matthew Renshaw is five not out in his first Test match since 2018 having tested positive for Covid-19 before play on day one.

Heavy downpours lashed Sydney on Friday morning and rain is forecast for the remainder of the day as well. Forty-nine overs were lost to rain and bad light on the opening two days to continue a run of rain-affected matches at the traditional SCG New Year's Test.

It has left Australia skipper Pat Cummins pondering over whether to declare early and before Khawaja has a chance to reach his double ton. Australia are keen on moving the match forward in their bid for a clean sweep of the series and to book a spot in the World Test Championship final in June.

Australia's formidable innings was built on a 209-run second-wicket partnership between Khawaja and Steven Smith. It was their 10th century partnership from just 33 innings and highest stand overtaking their 188 against England at the SCG in 2018.

Having moved past Sir Don Bradman on the career Test century list with his 30th ton, Smith fell for 104 while Marnus Labschagne and Travis Head contributed half-centuries.

A beleaguered South Africa have been out of answers as the spotlight shines on under-pressure captain Dean Elgar, who has seemingly been reactionary and conservative with his tactics.

Other than quick Anrich Nortje, who took the only two wickets to fall on day one, South Africa's attack has failed to penetrate with spearhead Kagiso Rabada particularly struggling. He has 1 for 119 from 28 overs to continue his underwhelming series.

South Africa need an unlikely victory to keep alive their slim chances of making the World Test Championship final although rain might help them avoid a series whitewash.

Sydney's forecast is better for Saturday with only a small amount of rain tipped before sunny conditions on Sunday.

The third day of the SCG Test is dedicated to Australia great Glenn McGrath's late wife, Jane, who died of breast cancer in 2008. But the traditional pre-match ceremony, which includes pink cap presentations to both teams, was moved to day four because of the weather.