Collingwood ruck-forward Darcy Cameron has been ruled out of the Magpies' clash with Fremantle on Saturday afternoon at the MCG.

Cameron departed Thursday's training session early with a hip injury, surfacing doubt over his ability to combat Dockers Sean Darcy and Luke Jackson on Saturday.

Cameron's exclusion from this weekend's side was confirmed following the session.

Cameron spent a stint on the sidelines early in the season due to a high-grade MCL sprain, with this hip ailment representing his latest setback this season.

Fellow ruck-forward Mason Cox has shared rucking duties with Cameron this season; hence, he looms as the most likely full-time ruck replacement for the 27-year-old this weekend, with utility Billy Frampton capable of chopping out to give Cox rest.

The Magpies' selected side to take on the Dockers will be announced on Thursday evening at 6:20 PM (AEST).

Collingwood's Saturday bout with Fremantle is fixtured for 1:45 PM (AEST).