Sydney will be without livewire forward Tom Papley for up to six weeks with an ankle injury, while two more Swans are no certainty to face the Western Bulldogs this weekend.
Papley was unable to finish Sunday's loss against the Lions due to a hurt ankle, with scans since showing medial ankle ligament damage that will place the small forward out of action for at least a month.
The news is more positive for veteran defender Dane Rampe (calf) and forward Will Hayward (ankle), who are both in the frame to play in Round 20.
Both Rampe and Hayward will need to prove their fitness at training this week to be cleared to face the Dogs, with selection calls to be made on the duo closer to Sunday's contest.
"Assessments today have confirmed forward Tom Papley sustained a medial ankle ligament injury against Brisbane and will likely miss 4-6 weeks of football," a club update read.
"Dane Rampe's calf tightness will be assessed by Sydney Swans medical staff on Tuesday.
"Will Hayward suffered a lateral ankle sprain in the 2nd quarter against Brisbane but continued to play out the match. He will be a test to play against the Western Bulldogs this Sunday."
The Swans aren't expected to have midfielder Justin McInerney back from a knee injury for another week at the very least, while a facial injury for James Rowbottom has him seen as no certainty to return this week.
Captain Callum Mills can be expected to come back into John Longmire's side after being managed, while Angus Sheldrick, Sam Reid, Aaron Francis and Caleb Mitchell may all be considered depending on the required changes for Round 20.
The Swans host the Western Bulldogs at the MCG this Sunday at 3:20pm (AEST).