Australia on the brink of winning 2nd Test against Sri Lanka after day 3 in Galle

Australia are two wickets away from ending Sri Lanka's second innings in the second Test Saturday, with the hosts reeling at 211-8 at stumps on day three in Galle.

With Sri Lanka leading by only 54 runs, Steve Smith's side will be eager to mop up the tail early Sunday and seal a 2-0 sweep.

Angelo Mathews was the linchpin of Sri Lanka's innings, holding things together as wickets tumbled at the other end.

But just 15 minutes before the close of play, he swept Nathan Lyon straight to square leg, where Beau Webster pocketed a sharp chance.

The 37-year-old warhorse had dug deep for a fighting half-century, but Sri Lanka needed a marathon knock, not his well-compiled 76.

Mathews finds himself in the crosshairs, with just one fifty in his last eight innings.

Ahead of this Test, the selectors had made it clear -- unless he starts churning out big runs, his spot in the next cycle of the World Test Championship was not fixed.

His sixth-wicket partnership with Kusal Mendis worth 70 runs was a lifeline for Sri Lanka, preventing an innings implosion and ensuring the game stretched into a fourth day.

Prabath Jayasuriya said Sri Lanka were "not out of it yet".

"Kusal Mendis is still out there and he has been batting well -- and if he can give us a decent lead, then we can put pressure on them," he said.

"It's not going to be easy batting in the fourth innings."

- 'Knock them over' -

There was an unusual moment in the afternoon session when a delivery from Lyon drifted down the leg-side.

It clipped the helmet placed behind the wicketkeeper for a close-in fielder, and triggered an automatic five-run penalty for Sri Lanka, a rare bonus in a match where runs were hard to come by.

With the picturesque Galle Fort providing a natural grandstand, hundreds of Australian supporters perched themselves atop the historic ramparts to enjoy a commanding performance from their side.

The fans celebrated as off-spinner Lyon became only the third Australian to claim 550 Test wickets, joining the exalted company of Shane Warne (708) and Glenn McGrath (563). 

Lyon was well-supported by Matthew Kuhnemann, sharing seven wickets between them.

Earlier, Alex Carey turned entertainer-in-chief with a swashbuckling 156 -- his career-best knock, peppered with 15 boundaries and two towering sixes.

While Smith (131) also took another big hundred -- his second of the series -- it was Carey who made batting look easy.

With Sri Lanka on the ropes and Australia poised for the knockout punch, day four promises high drama.

Kuhnemann said Australia still faced a "not easy" chase.

"Whatever they put up it will be tough," he said.

"It is going to turn a lot on day four, and we are looking forward to knock them over, score whatever the runs required -- and wrap up the series."

The visitors have already put the Warne-Murali Trophy beyond Sri Lanka's reach, having taken an unassailable 1-0 lead with a crushing victory in the first Test.

That innings and 242-run humiliation stands as Sri Lanka's worst defeat in Test history.