Sandilands missed the loss to North Melbourne last weekend with a heel injury diagnosed as plantar fasciitis.
General manager of football operations Chris Bond said that the club had been hopeful that Sandilands would be right for the Sydney game.
“Unfortunately, Aaron has not come up in time and will be rested for another week,” he said.
Bond also brushed off a report that Sandilands has a stress fracture in his left foot.
“We’ve said all along that it’s plantar fasciitis and that diagnosis has not changed,” he said.
Zac Clarke, Michael Walters and Byron Schammer have been named to take on the Swans.
The trio come in to the team at the expense of Rhys Palmer, Jay van Berlo and Justin Bollenhagen, who have all been omitted.
He had 26 hit-outs and 19 possessions playing predominantly in the ruck for East Perth.
Clarke will help take on in-form Sydney ruckman Shane Mumford.
Ironically, Mumford missed Fremantle’s round 9 win over the Swans earlier this season when Sandilands had 35 hitouts.
Schammer also stood out in round 20 of the state competition, winning Fremantle's WAFL player of the round award after a strong performance in the midfield for Claremont, where he has averaged 25 disposals in 15 games this season.
Both Clarke and Schammer have played only one AFL game this season - in the same match against St Kilda at Subiaco Oval in round 12.
Walters has also been rewarded for his consistency at WAFL level.
He travelled to Melbourne as an emergency in round 19 after a 28-possession, two-goal game for Swan Districts the previous week.
Senior coach Mark Harvey said his team would have to be on full alert for a Swans outfit looking to send off several champions on a winning note this year.
"There's obviously a lot of significance to what they're doing, Brett Kirk's last year and Roosy's (coach Paul Roos) last year," Harvey said.
"So there's all of that on top of where we are situated on the ladder.
"We've got an understanding of how important the game is.
"We need to put our stamp on the Swans when they get there."
Harvey said his team would take confidence from the fact it had already beat the Swans this year on a ground Freo has tasted minimal success at in the past.
"We played them earlier in the year and that was on a small ground which was the SCG and we matched them in that area," Harvey said.
"We managed to win that game.
"So the other question is can Sydney keep sustaining what they're doing (given it's) round 19.
"We'd like to think ... we can assert ourselves and dominate the mindset of Sydney from other aspects of the game."
The winner of Saturday’s clash between Freo and the Swans will take home the Redkite Cup.
A charity partner of both clubs, Redkite supports children, young people and their families through cancer by providing emotional support, financial assistance and educational services.
The inaugural Redkite Cup match took place in round 19, 2008, when Sydney won the honours at the SCG.
Fremantle bounced back to defeat the Swans at Subiaco Oval in round 5, 2009, and retained the cup with a win at the SCG in round 9 earlier this season.
Freo’s players have shown their support for Redkite by visiting children in hospital oncology wards, organising and participating in family days and participating in fundraising and community events.
Fremantle team
Backs: Dylan Roberton 24 Antoni Grover 14 Greg Broughton 6
Half Backs: Stephen Hill 32 Luke McPharlin 18 Roger Hayden 43
Centre: Garrick Ibbotson 5 David Mundy 16 Nat Fyfe 13
Half Forwards: Byron Schammer 3 Matthew Pavlich 29 Michael Walters 38
Forwards: Adam McPhee 9 Michael Johnson 37 Matthew de Boer 40
Followers: Kepler Bradley 26 Nick Suban 8 Paul Duffield 41
Interchange: Paul Hasleby 4 Anthony Morabito 2 Jessie Crichton 44
Zac Clarke 30
Emergencies: Justin Bollenhagen 27 Clancee Pearce 46 Jay van Berlo 47