As Australia's bowling attack look to work out how they can extract a victory from a batsman's paradise against Sri Lanka at Manuka Oval, it's time he became one again.

Starc (1-32) looked out of sorts in his initial spell before generating serious heat late on day two, peaking at 153/7kph as Sri Lanka ground their way to 3-123 at stumps, 411 runs in arrears.

The final three days present one last chance for Starc to stand tall as questions hover over the tearaway quick's place in the Australian side for the Ashes.

Starc's numbers throughout a gruelling summer are not awful - 15 wickets at 36 leading into this clash - however raw numbers do not tell the full tale.

Inconsistency has left the 29-year-old in danger of having his fast bowling cartel membership revoked, despite the repeated backing of his teammates.

However the man of the hour in centurion Kurtis Patterson has backed Starc to return to his best and rip through the Sri Lankan side to give the hosts a handsome first innings lead.

"Our attack is absolutely world class, Patty [Cummins] and Jhye [Richardson] just putting it on a spot like they do but putting it on a spot at over 140kph mind you, and obviously Mitch getting some rhythm," Patterson said.

"I'm not sure what [Dimuth] Karunaratne is going to do [on Sunday] but we're two wickets away from the bowlers. The way the game has gone, there has generally been a little bit in the wicket for the first 30-40 minutes of each day.

"If we can get a couple of early wickets and wind Starcy up and get into their tail, it'll go a long way to hopefully winning the Test."

Sri Lanka opener Karunaratne is in doubt after he was hospitalised after being struck on the back of the neck by a Cummins bouncer which left his father and sister visibly distressed in the stands.

It took almost 11 minutes for Karunaratne, who retired hurt on 46, to be taken from the ground on a medicab after he fell to bring a hush over the 11,388-strong crowd.

Cummins managed to bounce back soon after while off-spinner Nathan Lyon looked threatening on the deck he once called home.

For proof of just how hard it is to take wickets on a flat Manuka Oval track, look no further than the admittedly undermanned Sri Lankan attack.

Pace bowlers Kasun Rajitha (1-103), Vishwa Fernando (3-126) and Chamika Karunaratne (1-130) struggled for answers as the floodgates opened in Australia's search for a centurion.

Spin options proved futile as Joe Burns (180), Travis Head (161) and Patterson (114 not out) made Sri Lanka pay for dropped chances to steer Australia to 5-534 (declared).

"Especially on a track like this and when we have a young bowling attack, it hurts us more," Sri Lanka coach Chandika Hathurusingha said.

"It's very hard to create opportunities on this type of track and the quality batsmen don't give you many opportunities, it's really hurting us, dropping catches.

"We've had an unfortunate few injuries, especially within the space of two weeks, we lost our main three bowlers. Injuries can happen, you can't plan for those, we managed them as much as we can.

"We're trying to managed as best as we can at the moment."