Thanasi Kokkinakis concedes his debilitating pectoral muscle injury will likely force him to pull out of his hotly-anticipated 'Special Ks' doubles reunion with Nick Kyrgios.

While Alex de Minaur will headline the Australians in action on Thursday, there had also been much anticipation surrounding the doubles action pencilled in for the night session.

Kokkinakis and Kyrgios, the 2022 champions, were scheduled to play countrymen Aleksandar Vukic and James Duckworth in their first-round match on Thursday night.

Both had previously publicly stated their commitment to seeing through a doubles return after capturing the nation's attention on their blistering, fun-loving run to the title.

"Yeah, me and Thanasi, I think we owe it to each other to go out there and play," Kyrgios had said after his singles first-round exit.

But unfortunately, reality is about to get in the way again.

While Kyrgios's injuries were the problem over the past two years, this time it's Kokkinakis set to pull the pin.

Kokkinakis battled with his pectoral trouble during his marathon second-round loss to No.15 seed Jack Draper and later confirmed it was a long-standing issue that had him going through "mental torture and physical torture".

He conceded he would probably have to pull out of doubles as another long stint on the sidelines awaits.

"I feel like I'm letting him (Kyrgios) down, I'm letting people down but yeah, I don't know," Kokkinakis said on Wednesday night.

"I won't be able to lift my arm tomorrow. So we'll see.

"Unless we're both playing with underarm serves, it's looking pretty unlikely."

If he had won, Kokkinakis would have played Vukic, who had a heart-filled win over Sebastian Korda, in the third round.

For his part, Vukic has no plans of pulling the pin, despite his first trip to the final 32 of a grand slam.

"Me? No, no. I just talked to my partner, Duckworth," Vukic said.

"We were like: 'We good? We're good. Let's go.'

"So no chance."

World No.8 de Minaur will get to grips with American Tristan Boyer - who is making his Rod Laver Arena debut - as he attempts to reach the last 16 for the fourth time.

Aussie wildcard Tristan Schoolkate has the ominous task of facing reigning champion and world No.1 Jannik Sinner under lights on Rod Laver Arena.

Fellow wildcard James McCabe, 21, is due to play American Alex Michelsen on court three.

Elsewhere the only local woman left in the draw, Destanee Aiava will hope to continue her surprise career resurrection when she takes on big-hitting No.10 seed Danielle Collins on Kia Arena.

Fellow former champions Jason Kubler and Rinky Hijikata will kick off their campaign against top seeds Marcelo Arevalo and Mate Pavic.

In the women's doubles, local Ellen Perez and Belgian Elise Mertens, the sixth seeds, take on Australains Jaimee Fourlis and Petra Hule.

KEY AUSSIES IN ACTION ON DAY FIVE OF THE AUSTRALIAN OPEN ON THURSDAY (prefix number denotes seeding):

* Women's singles, second round:

Destanee Aiava v 10-Danielle Collins (USA)

* Men's singles, second round

8-Alex de Minaur v Tristan Boyer (USA)

Tristan Schoolkate v 1-Jannik Sinner (ITA)

James McCabe v Alex Michelsen (USA)