Johnson remains troubled by the foot injury that saw him ruled out of the Cats' win over Carlton in round 21 and their loss to Hawthorn last weekend.
Although his condition is improving, the club will be taking no chances given the finals are just around the corner.
"There's every chance that he could be right to play and we just leave it another week," Geelong coach Chris Scott said on Tuesday morning.
"Again, our medical staff will make really good decisions there. We're not pressuring them one way or the other.
"And there's plenty of time to work out whether we play him this week or wait until the week after.
"But all the early indications are very positive, so we're very, very confident that he'll be right for the more important game in two weeks."
Johnson didn't take part in the Cats' light training session on Tuesday morning, with Scott confirming that at the moment he was doing "not much".
"But that's been by design," Scott added. "It is a little bit hard to assess, because it’s one of those things that feels perfect when you're not doing anything.
"The test is when you actually start training, and he hasn't really done that yet."
For his part, Johnson is upbeat about his prospects of playing in the finals.
"It's feeling all right," he told Fox Sports News after arriving at the Cattery for treatment.
"I'm walking pretty comfortably now, so it's just a matter of progressing it over the next week or two.
"(I’m) pretty confident I'll be right for the first final."
The Cats are likely to rest a few first-choice players for the clash with the Lions, with Hamish McIntosh and Steven Motlop among those set to be given the weekend off.
"We'd be crazy to risk any players. That's the bottom line," Scott said.
"But we don't see any need to flirt with our structure too much.
"On balance, I'd say we'll be slightly more conservative this week than we were last."
With emerging key forward Shane Kersten sidelined by the hamstring injury he suffered against the Hawks, Mitch Brown and Josh Walker are both in the mix to take on the Lions.
Brown could replace Kersten, while Walker has been rucking strongly in the VFL in recent weeks, so he might be given the task of taking on the Lions' in-form big man Stefan Martin.
"We also have some younger players that have been on the periphery for a while: Bews, Smedts, Darcy Lang.
"Lincoln McCarthy's played a bit of footy in the VFL now and was very impressive on the weekend, so he'll come into calculations as well."
Poor performances after half-time continue to be an issue for Geelong, and the most stark example yet occurred on Saturday night at the MCG.
The Cats led by Hawthorn by 33 points early in the third quarter, before the Hawks piled on 10 unanswered goals.
"The fact that (second half fadeouts) have been a bit of a trend through the season means you have to look at it, and we certainly have to confront it," Scott said.
"We've definitely got a high degree of confidence that it can be remedied."
But will teams now back themselves to overrun the Cats in games?
"I think they will," Scott said. "I think they'll think that, but I reckon the psychological thing is a bit overrated, personally.
"I reckon what you do is a lot more important than what you think.
"But if we are going to focus on the psychological part, when the game's tight and in the balance … we’ve got a quiet confidence as well."
