Fremantle giant Aaron Sandilands is in doubt for Friday night's blockbuster against Carlton, with coach Ross Lyon confirming the ruckman is dealing with a knee complaint.

Speaking on radio station 6PR, Lyon said the 211cm ruckman suffered the injury after the Dockers win over St Kilda in Melbourne last Friday.

"He sort of just tweaked his knee a little bit after the game which just bled down a little bit into his calf," Lyon said

"He's basically told me he'll play but there's obviously a little element of doubt.

"He's got such a big heart and (he's so) mentally tough that I'd be surprised if he doesn't play."

Sandilands missed all but one of Fremantle's pre-season games after a calf complaint limited his training load.

His omission through injury would put the Dockers in a precarious position on Friday night with back-up ruckman Jonathon Griffen leaving the field with an