Melbourne defender Steven May could be out of action for a month because of a fractured eye socket, while Collingwood vice-captain Taylor Adams will spend 10 weeks on the sidelines.
May was rushed from the MCG to hospital on Sunday after copping an accidental elbow to the face from Geelong spearhead Tom Hawkins.
The Demons have confirmed May suffered both a concussion and fractured eye socket, also posting a photo of the backman's badly swollen eye.
May is out of hospital, with the club indicating he will miss between two and four weeks.
The Demons, undefeated amid their best start to a season since 1994, face Hawthorn, Richmond, North Melbourne and Sydney in coming weeks.
Adams may need to undergo knee surgery after scans revealed he suffered a medial collateral ligament (MCL) strain in the Magpies' loss to GWS.
Collingwood expect the midfielder to be out of action for 10 weeks.
The news is better for Jordan De Goey (shoulder) and Steele Sidebottom (thumb), who should both be fit for Pies' crunch clash with West Coast in Perth on Friday night.
Meanwhile, Port Adelaide young guns Xavier Duursma (knee) and Zak Butters (ankle) will both go under the knife after sustaining injuries in their team's dramatic win over Richmond.
Duursma expects he will miss 10 to 12 weeks.
"It was an awkward landing and I knew something wasn't right, I knew straight away," Duursma told 1071 SAFM.
"I have done the lateral ligament, the LCL, on the outside part of my knee."
