Rain dampens Australia's hopes of sweeping South Africa off the series

Steady rain threatens to derail Australia's bid of a series clean sweep against South Africa and a confirmed place in the world test championship final as the third and final test against South Africa at Sydney Cricket Ground meanders towards a draw.

After rain delays on both the first two days, further rain Friday meant no play was possible before lunch with Australia unable to add to its imposing first innings score of 475-4 and leaving Usman Khawaja on his overnight score of 195 and tantalizingly close to his first double century.

With more showers expected Friday, Australia has the dilemma of deciding how many runs it needs and then how much time it needs to bowl out South Africa twice on a pitch not yet offering the expected assistance for the spinners.

Australia has already won the series after two crushing defeats in the first two tests at Brisbane and Melbourne.

A win for Australia in this third test would confirm its place in the world test championship final to be played