Johnson, who has been dogged by foot soreness for the best part of a month, pressed his case by taking part in the Cats' main training session for the week at Simonds Stadium on Wednesday morning.
But the 31-year-old remains a 50-50 proposition to take on the Kangaroos.
"He trained OK today," Geelong coach Chris Scott told AFL.com.au on Wednesday afternoon.
"We still haven't made a decision on whether we'll play him or not.
"But right at the moment we're not treating him any differently to any of our other players.
"There's no need for a fitness test. He trained and now we'll make a good decision, hopefully."
Midfielder Allen Christensen, who missed last week's qualifying final loss to Hawthorn due to back soreness, is all but certain to be sidelined again this weekend.
Christensen trained away from main group on Wednesday.
"We still haven't made a decision on Allen," Scott said. "We meet later on this afternoon and we'll talk about that a little bit more.
"But I suspect our position with Allen will be to wait another day or so to make a final call."
In better news for the Cats, Steven Motlop has been declared a certain starter after recovering from the bruised shin he suffered against the Hawks.
"If he's not 100 per cent, he's virtually there, so our expectation at the moment is that he will play," Scott said.
