Off spinner Nathan Lyon dazzled on his international debut by capturing five wickets as Australia bowled out Sri Lanka for a paltry 105 runs in their first innings of the opening test.
Australia were 115 for six wickets at the close of the second day in their second innings with an overall lead of 283, leaving the home team facing an uphill task to save the match with three days still to go.
A limp batting performance by Tillakaratne Dilshan's men, with only four players scoring double figures, has left them trailing on a Galle pitch that has historically favoured spinners, especially in the last two days of a game.
In Australia's second innings, improved Sri Lankan bowlers dismissed opener Shane Watson with the very first ball and Ricky Ponting (4) in the fourth over.
Australian captain Michael Clarke held the innings together and shared a 56-run third wicket partnership with Phillip Hughes and 49 for the fourth wicket with Michael Hussey. He finally succumbed on 60 to the spin of Rangana Herath.
Earlier in the day when Sri Lankan were batting, Lyon enjoyed an unforgettable start to his test career when he removed in-form Kumar Sangakkara off the first ball of his debut over.
"I wouldn't say it was a perfect ball, but I was happy at the end," a delighted Lyon told reporters.
The 23-year-old finished the innings with five for 34 to record his best bowling performance in any form of cricket.
He dismissed the last four Sri Lankan batsman in just 12 balls for four runs to leave the home team in tatters.
Sri Lanka were never comfortable as the disciplined Australian bowlers made it difficult for them to score runs.
Before Lyon's heroics, all rounder Shane Watson bamboozled Sri Lanka's formidable middle order by trapping Thilan Samaraweera (26), Prasanna Jayawardene (0), and opener Tharanga Paranavitana (29), lbw within 10 balls.
IN TROUBLE
As Sri Lanka slumped from a relatively comfortable position of 87 for three to 88 for six, they never recovered from the shock and their innings soon folded.
"It is disappointing. We have to learn from the Australians," Sri Lanka coach Rumesh Ratnayake told reporters.
"We are looking at options how best we can attack Nathan Lyon. He bowled a good line and he insisted on that line and his line and length were impeccable.
"Hopefully, we will have out them for less than 140 and have our best shot going."
In the second over of Sri Lanka's innings, debutant paceman Trent Copeland removed opener Dilshan (4) with the second ball of his test career after the home captain had smashed a boundary off his first.
Dilshan had been hoping to give 25-year-old Copeland a rude introduction to the test arena with a show of aggression but after his initial blast, the Sri Lankan gave up a smart catch to Ricky Ponting at cover.
A subdued Sangakkara then batted for an hour to score 10 runs from 40 balls before being caught by Clarke with an excellent low catch at slip off Lyon's first ball in the 16th over.
Mahela Jayawardene, who joined opener Tharanga Paranavitana for the third wicket, tried to accelerate the pedestrian run rate but was run out for 11 by Copeland as he attempted an unnecessary single, leaving the hosts in trouble at 44-3.
Only Paranavitana resisted the Australian advance, facing almost 20 overs alone, but scored only 29 runs.
The tourists beat Sri Lanka 3-2 in the one-dayers ahead of the three-match test series.
