COLLINGWOOD defender Nathan Murphy is not contemplating retirement despite remaining on a modified training program indefinitely due to ongoing issues surrounding concussion.

The 24-year-old insisted he has not suffered a fresh setback but said he was not in the "right frame of mind" to take part in match simulation sessions.

Collingwood is not putting a timeline on Murphy's slated return to play.

"It was a pretty whirlwind off-season for me," Murphy said of suffering a serious concussion in last year's Grand Final win.

"I'm still really healthy; still participating in a lot of stuff.

"I'm not really contemplating retirement. That's not really on my agenda.

"I'm just trying to focus on getting back out there to play football."

The premiership player was examined by the League's concussion panel and was ultimately given the green light last December to resume playing.

Collingwood had asked the AFL to assess the 57-gamer's condition, noting he had suffered multiple concussions prior, and after, starting his AFL career.

"I had a really good assessment with the panel and they're professionals in this area so I trust their opinion," Murphy said.

"I know I'm in a really good spot, it's just probably more of a frame of mind sort of decision at the moment.

"It's just making sure I'm ready to approach the season and ready to play competitive football."

Murphy sent a scare through the Collingwood camp on Wednesday when he was assessed at training following a strong tackle from Magpies superstar Nick Daicos.

He was immediately cleared by medical staff and there were no further issues from the incident.

"It was good to see Nick laying a tackle for once, that doesn't matter too much," Murphy joked.

"But I actually responded really positively to that.

"I think in the footage I actually get back out there and train so that incident had nothing to do with any of this."

Collingwood football boss Graham Wright, who is about to embark on a six-month sabbatical, completely supported Murphy's decision.

"We've been in discussions over the last couple of weeks," Wright said.

"Nathan's healthy, feels really good.

"But from a mental wellbeing place, he's made a decision to withdraw himself from the match-sim part of training and games until further notice."

Collingwood plays a match simulation game against North Melbourne at the AIA Centre from 10am AEDT on Wednesday, February 21, before a practice match against Richmond on Tuesday, February 27 at Ikon Park from 6.40pm AEDT.