The Dockers (11-1) are on top of the AFL ladder and riding a club-record 11-match winning streak heading into Saturday's clash with North Melbourne in Bunbury - a country town 175km south of Perth.
Although Caleb Serong will miss a third straight game with a calf injury, Fremantle are set to be boosted by the return of fellow star midfielder Hayden Young from concussion.
Matthew Johnson (hamstring) has also been cleared to play after suffering a scare in last week's 25-point win over Brisbane.
But coach Justin Longmuir is leaning towards playing it safe with Cox, who copped a knock to the knee in the same game but has escaped injury.
"Coxy is an interesting one," Longmuir said before training on Thursday.
"With the bye next week, is it an opportunity to give him a couple of weeks off to try and get that knee right?
"He'll see how he feels after training and make a call on that one."
If Cox doesn't take on North Melbourne, Oscar McDonald is set to come back into the team after doing a strong job filling in while Alex Pearce was recently sidelined.
Fremantle's enviable depth and excellent start to the season means they can afford to ease players back in rather than rush them back.
It's why both Darcy and O'Meara will play at least another week in the WAFL.
Darcy played the first five games of the season before being cut down by a concussion and then another calf injury.
O'Meara, who featured for WA in this year's State of Origin, suffered a horrific facial fracture at training in the week following the round-five victory over Collingwood.
Darcy made a successful return via the WAFL last week, while O'Meara has spent the past two weeks in the seconds.
"I think the luxury we have at the moment is making sure we get JOM (O'Meara) right after a nasty incident, a smashed face really," Longmuir said.
"After six weeks out, to be able to build his form and fitness and confidence a little bit slower and not having to rush him back is a good space to be in.
"It's a little bit like Sean. Sean's a quality AFL player, but we've got luxury at the moment with our depth and where we see it to be able to build their form and make sure that when they come in the team, they're ready."
North Melbourne (5-6) will be without tagger Finn O'Sullivan, who will miss the next two matches after being concussed at training this week.
