The 31-year-old, who holds the record for the most games played without a final, has not appeared on the field since round 20's win over the Brisbane Lions.
He is suffering from a syndesmosis injury to his right ankle, which affects the ligament that connects the tibia and fibula bones.
It's also known as a high ankle sprain with the recovery usually expected to double that of a normal sprain.
He had a setback at training last week but was hopeful of being named to face Essendon on Saturday night.
Now, after missing the win over the Bombers, he will need to prove his fitness this week if he is to play in next week's final – likely on Sunday against Carlton – and remains optimistic he can do it.
"It's pretty good. It's progressing well; it's kind of caused me a little bit more trouble than I'd expected," Newman told AFL.com.au.
"It's just one of those things that I just have to manage and make sure it's 100 per cent.
"Obviously when you get an injury around your ankle, it's hard to avoid with the amount of times you have to use it throughout the game.
"I've just tried to get it as right as possible and hopefully I can come back and not have any more trouble with it."
Newman said he "did a bit of damage" to that important ligament that joins the two leg bones but understood he escaped what could have been a more serious complaint.
"I was lucky it wasn't too much damage because there have been a few boys who have been sidelined from it that have had more extreme cases," he said.
"I've just done a little bit of damage to the outside of the ankle as well.
"It's all progressing really well so I should be fighting fit soon."
Newman isn't sure if he'll need surgery after the finals, which would signal the first time he would go under the knife in a post-season situation.
He knows he just needs to prove himself at training but has acknowledged the challenge in front of him having missed the past three weeks.
"It's not an ideal preparation going into our first finals series in so long but no doubt I just have to keep my fitness up and just keep some touch so I don't lose too much and I'm ready to come back in," he said.
"It's feeling good and hopefully it just goes away."
On Thursday, coach Damien Hardwick said there was no reason to risk players at this stage of the season before they decided not to name Newman for Saturday night's game.
He also while there was "no sentiment in AFL footy", the former captain's experience would mean he would be a starter next week if he got through training.
"If he's fit to play, he'll play. We've just got to make sure he's fit," Hardwick said.
Twitter: @AFL_JenPhelan
