India 150 (Hazlewood 4-29) and 487 for 6 dec (Jaiswal 161, Kohli 100*, Rahul 77) beat Australia 104 (Bumrah 5-30) and 238 (Head 89, Bumrah 3-42, Siraj 3-51) by 295 runs
Completing a remarkable turnaround, India wrapped up a famous Test victory at Optus Stadium with a 295-run victory over Australia in a one-sided result set to cause aftershocks in the latest tussle for the Border-Gavaskar Trophy.
The result was essentially a formality throughout the fourth day despite counterattacking knocks from Travis Head and Mitchell Marsh. India's deserved victory was official just after tea when Harshit Rana knocked over Alex Carey as they drew first blood in the five-match series.
It was a memorable performance from India, who drew on a heroic effort from stand-in captain Jasprit Bumrah. He claimed eight wickets for the match, while Yashasvi Jaiswal and Virat Kohli produced outstanding centuries in India's second innings to decimate a flagging Australia.
India had largely been written off after an unprecedented 3-0 home whitewash against New Zealand. They entered the series-opener without having played an official match on tour and were shorthanded without captain Rohit Sharma and injured batter Shubman Gill.
Under intense pressure, coach Gautam Gambhir made the right moves and the brave selection calls, which included veteran spinners R Ashwin and Ravindra Jadeja being left out, were vindicated.
Bumrah, particularly, deserves a lot of credit for galvanising a new-look team and he led from the front with a mesmerising spell late on day one to haul India back into the match after they had been bundled out for 150 having won the toss.
There is set to be recriminations for Australia, who underwhelmed in their first Test since March's New Zealand tour. There will be questions raised over the limited preparations of a number of players.
Australia's misfiring top-order will be particularly under the spotlight, especially No. 3 Marnus Labuschagne who scored 5 runs in the match to continue a lengthy form slump.
Having started so well on the opening day, Australia's bowling wilted in India's second innings with captain Pat Cummins enduring a rare off match. Cummins had not played a red-ball match since March, preferring his series build-up through three 50-over games in the lead-up, and he finished with the modest match figures of 3 for 153 from 40.4 overs.
Australia appeared flummoxed with the changing conditions of the pitch, which was spicy on day one before flattening out for most of day two and three. Cracks did widen as the match wore on and created up-and-down bounce to make batting difficult on the fourth day.
Resuming at 12 for 3, after a disastrous start amid the shadows late on day three, Australia confronted an India attack eyeing to finish things off quickly.
Australia's hopes of chasing down a record 534 runs were forlorn but they aimed to at least muster some spirit which had seemingly been broken over the last couple of days.
After a golden duck in the first innings, having returned to his favoured No. 4 position, Steven Smith fronted up to his nemesis Bumrah, who on the first ball of the day's play had a loud lbw appeal turned down although in an anti-climax it was a no-ball.
Smith was relieved when he got off the mark on his fourth delivery with a trademark drive through the covers. But Australia's woes reared in the next over after opener Usman Khawaja fell off the first short ball of the day's play when he top-edged quick Mohammed Siraj and was caught by wicketkeeper Rishabh Pant running back.
Having had lbw issues recently, Smith made a technical adjustment and his trigger movement was not as pronounced as in the first innings when Bumrah pinned him in front of the stumps. Smith still faced a battle and copped a painful blow in the ribs from debutant quick Rana that left him on his back and in agony.
He bravely continued batting and combined well with Head, who backed his aggressive instincts and counterattacked as they produced Australia's first half-century partnership of the match.
India dried up the scoring for Smith with Bumrah packing the legside with fielders as pressure built. Smith's 60-ball resistance ended when he nicked off a superb back of a length delivery from a pumped-up Siraj that straightened off the seam and caught the edge.
After a tough return to bowling, where his modestly-paced seamers were treated with disdain on day three by India's batters, Marsh hoped to finish his home Test match strongly.
He was all at sea before the lunch break and hit on the gloves several times but managed to hang in. Marsh and Head, who both entered the match with a limited build-up having been on paternity leave, made batting look relatively easy after the interval in a time of day that had been the best for batting through the match.
Head motored towards a century and as per usual attacked any width and continually flayed through the offside, while Marsh struck several lusty aerial blows in a speedy half-century partnership.
But Bumrah returned and he produced a superb back of a length delivery that caught Head's edge on 89 and prompted impassioned celebrations from Kohli.
Marsh also missed a milestone when on 47 he chopped on to allrounder Nitish Kumar Reddy, who capped an impressive debut with his first Test wicket.
Mitchell Starc was sharply held at short leg, giving Washington Sundar his first wicket of the match, and it wasn't long before India claimed a victory they will saviour for some time as the pressure starts to intensify on Australia.
