A foot stress fracture meant the former Demon ruckman couldn't push his case for inclusion on the playing list on the track and, while he's back running now, he won't play any football for eight weeks while he completes a mini pre-season.
"I could probably play now if they allowed me to, but it's going to be a slow process to make sure I get fit enough," Johnson says.
"I think they just want to be on the cautious side and get me ready, in case they need me in the second half of the season.
"It's been a long six months, but I'm really excited by this opportunity."
Johnson, 26, admits he was frustrated to remain confined to the rehab group as the weeks rolled by and the Hawks' selection panel considered the best fit for the final spot to be decided after the NAB Cup grand final.
But, while he couldn't get out on the track and show them his eagerness to claim the spot, he found other ways.
"I was pretty lucky in my situation because they know what I can do football-wise, so it was more about showing the attitude that I wanted to be there and I wanted to get back on a list," he says.
"All I could do was work flat out with my rehab to make sure I did everything I possibly could to get my foot recovered. Just doing all the small things that showed I was committed to it 100 per cent.
"I watched a lot of training and tried to pick up the game plan and the way they do things. So I walked into the club after they made the decision and had a fair idea about the game plan and where things are going."
While Johnson understands the harsh reality of modern day AFL list management, he says it didn't make the Demons' decision to cut him after 69 games any easier to stomach.
He was delighted to be offered the opportunity to join Hawthorn's 'train-on' squad over the summer, but adds the initiative the AFL brought in for the first time at the end of last season was a difficult one to negotiate.
"It's all worked out well in the end, but it is a long process," he says.
"You find out in early December that [you've got this opportunity] but you don't find out what you're going to be doing until the middle of March.
"You have to go through all the process of where you'd play if you don't get picked up, and if you do get picked up, what are you going to do with work.
"It was pretty awkward at times because you're training with a group of guys and you're not sure if you're going to be there for three months or a whole year. But Hawthorn was fantastic and allowed me to keep working the full-time job, I'd had since late last year and it all worked well."
Johnson admits it has been a strange summer, but having finally joined good mates Cameron Bruce and Kyle Cheney at the Hawks, he feels his best footy is still in front of him.
"If I'm going to do something, I want to do it flat out and not leave any stones unturned. That's been my process at Hawthorn," he says.
"I had a pretty rough year with injury last year, but the games I did play in the VFL, I thought I played pretty well and I still think I've got a lot to offer at AFL level.
"Hopefully when I start playing for the brown and gold I can show that I have more to offer again."
