Sam Docherty during Carlton's match against North Melbourne in R4, 2023. Picture: AFL Photos

CARLTON has suffered a significant blow, with star defender Sam Docherty undergoing surgery to repair a torn meniscus in his knee on Tuesday that is expected to keep the former captain sidelined for up to six weeks.

Docherty reported soreness over the weekend following the club's Good Friday victory over North Melbourne, with scans on Monday revealing a tear in his meniscus that forced surgery just 24 hours later.

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The Blues expect him to miss between four to six weeks, softening the positive news from Ikon Park that star midfielder Sam Walsh is likely to return from an ongoing back problem this week.

Walsh has been dealing with a back issue all summer after aggravating the injury last August, but trained fully on Tuesday morning and is expected to be named for Thursday night's Gather Round opener against Adelaide.

Sam Walsh kicks the ball during Carlton's clash against Fremantle in round 15, 2022. Picture: AFL Photos

Matt Kennedy (calf), Mitch McGovern (thigh) and Jack Martin (calf) also completed Carlton's main session on Tuesday and should be available for this week, while Blake Acres has recovered from a pectoral injury he dealt with during his one-match ban.

The Blues have also been integrating Jordan Boyd and Matt Cottrell back into full sessions recently, with the club hopeful of regaining the pair over the next fortnight having dealt with respective foot injuries since before Christmas.

Carlton will challenge a one-match striking ban handed down to former Coleman Medal winner Harry McKay at the AFL Tribunal on Tuesday night, following an incident involving North Melbourne youngster Harry Sheezel last Friday.