Australia's Matthew Kuhnemann bowls a delivery during day four of the first test cricket match between Sri Lanka and Australia in Galle, Sri Lanka. (AP )

GALLE, Sri Lanka, Feb 1, (AP): Australia wrapped up the first test against Sri Lanka with a session and a day to spare, handing the hosts their biggest defeat in test cricket on Saturday.

Sri Lanka was skittled out for 247 in their second innings, succumbing to an innings-and-242-run drubbing. Their previous heaviest test defeat was an innings-and-239-run loss to India in Nagpur in 2017.

Spinners Matthew Kuhnemann and Nathan Lyon ran riot, sharing 16 wickets between them as they dismantled Sri Lanka’s fragile batting lineup in both innings.

Kuhnemann, who had already snared a five-wicket haul in the first innings, finished with figures of nine for 149 - his best in test cricket.

"We started well with the openers setting the tone,” Australia captain Steven Smith said. "Usman (Khawaja) was amazing with that double hundred. He put a lot of pressure on the bowlers. Getting 650 allowed us to dictate terms.

"The first day didn’t quite reflect the score,” Smith added. "It took some spin and we batted exceptionally well. I thought we bowled well. The thing of having three spinners is that you can keep them fresh and the next guy can come and make an impact.”

Sri Lanka’s resistance was feeble at best. They lost eight wickets in a session before lunch and another seven between lunch and tea, as the defending world champion Australians stamped their authority with smart bowling and exceptional fielding.

Sri Lanka had allowed Australia to rack up a commanding first innings of 654 for six declared. Khawaja’s double century, Josh Inglis’ debut hundred, and Smith’s second test century propelled the visitors into a position of absolute command.