Hazlewood got through around 35 minutes of gentle bowling in the MCG nets on Thursday, still appearing in some discomfort on return from a side strain.

The session was Hazlewood's first bowling in almost three weeks, after hurting his side in the Ashes opener at the Gabba and missing the next two Tests.

With the series already wrapped up in Australia's favour there is some argument that Hazlewood should be given more time to recuperate.

But chief selector George Bailey said his panel would not hold Hazlewood back if fit.

"I've got pretty good faith in Hoff knowing his own body and trusting his own body," Bailey said.

"He'll build up as he would before any sort of Test.

"He'll talk a lot with (assistant) Andrew McDonald and (physio) David Beakley to see how he's going.

"If Hoff's confident and he says he's right to go I think we back him in. He's earned that trust."

Bailey also indicated that Australia's innings victory in Melbourne meant Mitchell Starc would not sit out Sydney, despite being the only quick not to miss a Test this summer.

Starc was required to bowl just 25 overs at the MCG and Australia's early win gave him day four and five off without even bowling in the nets and a week between Tests.

"Your plans are constantly changing because you've got no idea how many overs the bowlers are going to bowl," Bailey said.

"So you've got to stay pretty fluid around that

"Today would have been would have been day five (at the MCG).

"So our quicks, in particular, not having as heavy a workload as they had in Adelaide and a couple of extra days off will all work in their favour."

Skipper Pat Cummins, who missed the second test due to a COVID scare, is one paceman assured of playing.

If fellow regulars Starc and Hazlewood both play, it means there will be no room for debutant Scott Boland despite his stunning 6-7 performance on debut at the MCG.

Jhye Richardson would also miss out after sitting out the Melbourne Test with minor leg soreness following his match-winning five-wicket haul in Adelaide.

At best there could be room for one of them, creating a tough situation for selectors given Richardson was above Boland in the pecking order before Melbourne.

"That's a headache. It's a great headache," Bailey said.

"Obviously some hard conversations to be had at some stage."

The other spanner in the works could still be Mitchell Swepson, if Australia see a spinning wicket in Sydney and decide to play two tweakers, with allrounder Cameron Green as the third seamer.

"We've got no doubt that, whether it's at the SCG or whether it's sometime in the future, that Swepo is ready," Bailey said.

"We'd love nothing more for him to get an opportunity but it will probably be conditions-dependent."

Australian Associated Press