CARLTON star Sam Walsh's ongoing back issues have flared again with the Blues taking a 'no-risk approach' to his return, while forward Jack Martin (knee) is facing a race against the clock to be fit for the Blues' season opener against Brisbane in just over a fortnight's time.

Walsh experienced back soreness after an intense intraclub hitout earlier this week and has been placed on a modified training program ahead of the season opener.

The Blues' co-vice captain will not take part in the club's match simulation against Geelong on Thursday or their AAMI Community Series match against Melbourne next week, with a call to be made on his return ahead of the Blues' Opening Round clash against Brisbane.

"Sam experienced back soreness after completing match simulation last Monday. After further assessment it has been decided to reduce his training loads," Carlton footy manager Brad Lloyd said.

"We will take a no-risk approach with Sam's return to play, therefore he will not feature in the upcoming practice games, with the club to provide a further update on Sam's progress prior to our (Opening Round) clash against Brisbane."

The 23-year-old has battled back soreness for the last two years and underwent back surgery in December of 2022 to rectify the issue.

He played 18 of a possible 26 games last season and went on to play an instrumental part in the Blues' run to a preliminary final.

Martin is taking positive steps forward after suffering an MCL knee sprain, with the dynamic forward to return to full training next week.

The Blues are hopeful the 29-year-old will be available in 2-3 weeks, meaning he is an outside chance to play in Opening Round against Brisbane.

Carlton has already lost defender Jacob Weitering (calf) for the first part of the season, while a host of other names continue to battle injuries just a fortnight out from the start of the season.

Jack Silvagni has begun his rehab but will miss the entire season after rupturing his anterior cruciate ligament at training in January, while Corey Durdin (hamstring) and Matt Owies (calf) are touch-an-go for Opening Round.

Fellow defender Caleb Marchbank has increased his training loads after experiencing post-viral symptoms following an illness, with the club to determine his return to play once he progresses further in the training program.

Alex Mirkov (heart) continues to be in modified training with his return to play not yet known.