Australia require 14 more wickets on day five against South Africa if they are to finish the job at the SCG and collect a Test series sweep.
After a number of delays for rain and poor lighting over the first two days, the third day was completely washed out, forcing the Australians to declare after lunch on day four at 475-4 in order to chase a result.
It meant stranding hometown hero Usman Khawaja on 195 not out, but the hosts would get to bowl 59 overs in sharp turning conditions while the tourists could realistically only play for a draw.
Any South African dreams of a two-day batting stand to salvage a gutsy draw in the third Test took a blow when Josh Hazlewood (2-29) removed Dean Elgar for 15, drawing an outside edge through to the Alex Carey behind the stumps after returning from over a month out of the side.
Things went from bad to worse for South Africa when opener Sarel Elwee opted to leave an off-spinner from Nathan Lyon, only for it to clip his off-stump, departing for 18.
After captain Pat Cummins removed number-three Heinrich Klaasen caught behind for just two runs, the combination of Temba Bavuma (35 off 74) and Khaya Zondo (39 off 83) built a respectable partnership.
Ultimately the Aussie pace attack was too much to handle, with Hazlewood finding the edge of Bavuma before Cummins landed a yorker on Zondo's toes for a plumb LBW.
Cummins took one more in the fading light – Kyle Verreynne's edge to Steve Smith in the slips – to finish the day with team-best figures of 3-29 from 14 overs as South Africa finally reached stumps at 149-6, trailing by 326.
Khawaja reaches new heights at home ground
With his career-high 195no – his fourth not-out from 10 innings at his home ground – Khawaja raised his Test average at the SCG to 130.83.
It is the third-highest Test average for any batter with more than three innings at the ground, trailing only England's Wally Hammond (161.6 from seven innings) and India's Sachin Tendulkar (157.0 from nine innings).
Frank Worrell and Tendulkar are the only other batters in Test history to have been in the 190s when their captains declared.
Hazlewood illustrates Australia's fast-bowling 'problem'
Australia currently have an embarrassment of riches in the fast-bowling department, and it has reached a stage where an elite talent like Hazlewood is fighting for his spot.
Having not played for Australia since a Test against the West Indies in late November, Hazlewood reminded everyone just how good he is, finding the edge of both Elgar and Bavuma to put the hosts in a winning position.
With Scott Boland also boasting historic Test figures, as well Michael Neser and Lance Morris champing at the bit for their opportunity, it creates a good problem for the Aussies to have in an Ashes year.