Veteran Sydney defender Dane Rampe will miss the next month of the AFL season because of a hamstring injury.
The 33-year-old was substituted from the Swans' loss to Richmond on Sunday, with scans revealing a low-grade strain.
Rampe will miss three or four weeks, but the Swans were boosted by the news fellow stalwart Harry Cunningham could return for Saturday's Gather Round game against West Coast.
Cunningham was concussed in a round-two incident that led to Essendon's Peter Wright copping a four game suspension.
Port Adelaide will be without Brownlow medallist Ollie Wines for their Friday night fixture against Essendon.
Wines has a hamstring injury but his absence will be offset by the return from a similar problem of fellow midfielder Jason Horne-Francis, who has missed the past two games.
Adelaide utility Lachlan Murphy faces about five weeks out with a knee injury, joining teammate Wayne Milera on the sidelines.
Milera was on Monday ruled out for the rest of the season after rupturing the patella tendon in his right knee knee during Adelaide's loss to Fremantle on Friday, when Murphy damaged a lateral ligament.
"Murphy is going to be (out) anything up to three to five weeks with his knee injury," Adelaide coach Matthew Nicks said.
Hawthorn will be without key forward Mitch Lewis (hamstring) and rookie Nick Watson (ankle) for Sunday's clash against Collingwood.
The Hawks hope Lewis will miss just one game but Watson could be out for six weeks.
"Mitch won't be available this week given the six-day turnaround, but we will monitor his response to loading to determine his round five availability," Hawthorn's doctor Liam West said.
"Being a lower-grade injury we don't expect Mitch to miss a considerable amount of game play."
Watson's debut season will be curtailed after scans revealed the extent of his ankle problem.
"Fortunately in Nick's case, he won't require surgery on his ankle," West said.
"He'll spend the next period in a moonboot to allow his ligaments to heal before we begin loading him up again.
"At this stage, we think he'll be out four to six weeks but will continually reassess this during his rehab period."
