Fremantle is sweating on the fitness of star midfielder David Mundy and forward Chris Mayne heading into Saturday night's clash with Sydney at the SCG.

Mundy was subbed off with concussion in Sunday's 53-point win over Essendon after being collected by teammate Luke McPharlin.

Mayne missed the match with an ankle injury, and will have to prove his fitness at training this week if he is any chance to take on the Swans.

Fremantle will be boosted by the return of on-baller Nat Fyfe from suspension, but Michael Walters (ankle), Garrick Ibbotson (shoulder) and Michael Barlow (knee) are still at least several weeks away from returning.

Walters might miss a large chunk of the season if he ends up requiring surgery to fix the ankle he damaged against Hawthorn a fortnight ago.

Fremantle had 12 goalkickers in its crushing win over Essendon, with skipper Matthew Pavlich (three) leading the way.

Coach Ross Lyon was pleased with the even spread, believing his side was too focused on Pavlich a week earlier in the heavy loss to Hawthorn.

"We spoke about that - we bombed in to Matthew and they just had a plus one all day rolling off," Lyon said of the loss to Hawthorn.

While the Dockers are flying at 3-1, Sydney are in early trouble at 1-3 following an unusually lacklustre start to the year.

Swans forward Kurt Tippett is a chance to return against the Dockers, but star veteran Adam Goodes and Sam Reid are still at least a week away.