Big guns Cheteshwar Pujara and Virat Kohli steered India into a commanding position in the decisive fourth and final Test Thursday after an impressive 77 from young opener Mayank Agarwal.
At tea on day one, India were 177 for two with the dependable Pujara on 61, grinding out his fourth half-century of the series, and patient skipper Kohli not out 23 in what is shaping as an ominous partnership.
The visitors lead the series 2-1 after winning the opening clash in Adelaide and the third one in Melbourne. Australia claimed victory in Perth.
If India, the world's top-ranked nation, win or draw in Sydney they will clinch a first-ever series in Australia since they began touring Down Under in 1947-48.
Kohli again won the toss with KL Rahul back in the team to open with Agarwal and Hanuma Vihari dropping to number six to cover for the unavailable Rohit Sharma.
Australia got an early breakthrough with Josh Hazlewood tempting Rahul into a defensive shot that took a outside edge and carried to Shaun Marsh at first slip, and he was gone for nine.
But that only brought the stoic Pujara to the crease and like he has done all series, the 68-Test veteran dug in and blunted the new ball.
He survived a review decision for caught behind on 12, but was otherwise rock solid.
Pujara, who has faced more balls and scored more than anyone else in the series, slowly picked off runs, leaving any flamboyance to others, to bring up his 21st Test half-century in 134 balls.
Playing in only his second Test, the Bangalore-born Agarwal was also impressive.
He was targeted with bouncers and struck on the helmet but held firm, reinforcing his credentials after a solid debut in Melbourne.
He worked hard to make his second Test 50 in only three innings by caressing a Mitchell Starc delivery through the covers for four.
But he began to open up with the bat and after hitting Nathan Lyon for six to bring up his highest Test score of 77, attempted to do the same from the next delivery and was caught by Starc at long-on.
Master batsman Kohli was welcomed by boos from a section of the crowd and immediately silenced them with an exquisite four off Hazlewood.
But it was a restrained Kohli as he and Pujara look to build a big total and take the game away from Australia.
For Australia skipper Tim Paine, it was the sixth toss he had lost in seven Tests and it could prove costly on a Sydney Cricket Ground pitch expected to be conducive to spin as it wears.
When Australia bat, they will have a new look opening pair with Usman Khawaja padding up with Marcus Harris after the underperforming Aaron Finch was axed.
In a surprise throw of the dice, leg-spinning all-rounder Marnus Labuschagne was called up and will come in at three.
Mitch Marsh was also dropped with Peter Handscomb back to counter India's two spinners - Kuldeep Yadav and Ravindra Jadeja.