Sri Lanka on brink of Test series victory over Australia after 21-wicket day

Sri Lanka remained on course to secure a Test series victory over Australia after day two of the second match saw a total of 21 wickets tumble on a manic Friday at Galle International Stadium.

Chasing an improbable 413 runs for victory, Australia lost three wickets on a turning surface in just six overs, leaving captain Steve Smith (1) and David Warner (22) with a monumental task of staving off an embarrassing series defeat.

Responding to Sri Lanka's first innings score of 281, Australia were crippled by inept batting as they were bundled out for a record low of 106 after starting day two's play at 54-2.

Veteran spinner Rangana Herath was Australia's tormentor-in-chief as he claimed four wickets in the first innings including a hat-trick to rip the visiting batting apart. He was the second Sri Lankan to take a Test hat-trick.

Sri Lankan batsmen were also bowled out for 237 in their second innings after Mitchell Starc backed up his 5-44 in first innings with a career best 6-55, however, the hosts stretched the lead past 400.

Nathan Lyon bagged two wickets while Josh Hazlewood and Jon Holland claimed a wicket apiece in a match moving at a brisk pace.

For Sri Lanka, Dilruwan Perera was the top scorer with 64 while captain Angelo Mathews once again produced a crucial knock of 47.

Sri Lanka are leading the three-match series 1-0 after winning the opening Test in Pallekele.