CARLTON has decided to send Jack Silvagni for surgery, after the Blues forward hurt his troublesome right shoulder for the second time in a month during Saturday night's victory over Gold Coast.

Silvagni will undergo a minor procedure on his right shoulder on Thursday, which is expected to keep him sidelined for around a month, after injuring the posterior ligaments laying a crucial chase down tackle in the final quarter at Metricon Stadium.

It was the second time in four weeks Silvagni has hurt his shoulder while laying a tackle, having been substituted out of the side's round one defeat to Richmond before missing the following week.

Carlton has also decided it will send fellow forward Zac Fisher for surgery on his injured ankle on Thursday, after it was discovered the diminutive West Australian had a small bone growth in the area.

Fisher, who was already tipped to miss the next four weeks due to a bone stress issue in his ankle, will now have his recovery delayed by another month and isn't expected to feature before the midway point of the season.

The injuries are compounded by a back issue to fellow marking target Oscar McDonald, which is expected to keep the club's pre-season supplemental selection period signing out of action for around three months.

"Although we would have liked Jack to be available for this weekend, we feel this is the best approach to ensure he can return to the side this season and contribute to the high level he already has in the opening rounds," the club's head of football Brad Lloyd said.

"He will commence his rehab immediately following the procedure and we expect him to be available for selection again in a month.

"Zac's injury is unique, which is why we have explored every possible avenue over the last few weeks in regard to the best path of rehabilitation.

"After speaking with a surgeon today, it was decided this would be the appropriate course of action. Zac was originally expected to return in the next three to four weeks, we now expect this will extend that recovery time by a month.

"However, it will enable a better medium- and long-term outcome which is really important for both Zac and the club in regard to this season and moving forward."