Johnson is one of about eight players facing an uncertain future as the Cats look to continue ushering through emerging talent while maintaining a link to their premiership years.

Cats chief executive Brian Cook said at the weekend the club would have several tough decisions to make, suggesting three or four veterans would be retained.

Those under pressure include Corey Enright, Hamish McIntosh, Jimmy Bartel, James Kelly and Mathew Stokes, with the latter contracted for next season.

Defender Jared Rivers says he is "90 per cent sure" this will be his final season but Bartel seems almost certain to play on, with a contract extension imminent.

Johnson's indifferent form has been a source of great debate, with former Cats assistant coach Brenton Sanderson the latest to weigh in, declaring Johnson should retire.

"I understand it. People are paid to have an opinion. I certainly understand the fascination with where our list is at and the demographic, and there are plenty of older players and decisions will have to be made," Johnson said on Tuesday.

"My form has been a little bit like the rest of the team, a bit inconsistent, especially early on in the season. But I feel as if the body is getting better and better as the season goes on, given I had a bit of a mishap in the pre-season, and it really does hamper you.

"I am starting to feel a lot better, probably in the last three or four weeks."

Johnson, 32, endured a foot complaint over summer that restricted his pre-season training.

However, the three-time premiership star feels his form has improved, and he believes some pundits may not have understood the role he played against Western Bulldogs last Saturday.

"It's a little bit different. I am obviously not putting up the same numbers as I have in the past as a midfielder," he said on Radio Sport National.

"I have been playing as a half-forward and my role on the weekend was probably a little bit different – it was actually to nullify the influence of Easton Wood, who is having a fantastic season for the Bulldogs.

"That is a changing role that people probably don't notice on the outside but one I am happy to do for the team."

Johnson had 20 disposals against the Dogs but was held goalless for the first time since round two. Wood, who has been in All-Australian form as a rebounding defender, was voted among the Bulldogs' best but had only 15 disposals, his lowest since round 10 against Port Adelaide.

As the Cats look to remain in finals calculations, Johnson feels he still has enough to give to justify playing on next year, in what would be his 16th season.

"I do but I haven't ruled out anything at this stage. My focus is on playing some good footy towards the end of this year and then weighing up what I'll do at the end of that," he said.

"As I did mention earlier, I feel as if my body, especially in the second half of the year, is getting better and better, so we'll just see what happens."

If he was to retire, Johnson said he was keen to remain in the sport.

He is on the "next coach program", which West Coast Eagles coach Adam Simpson completed while playing for North Melbourne.