Geelong's return to form has been soured by confirmation premiership stars Tyson Stengle and Rhys Stanley will undergo surgery that will put them out of action for several weeks.
Scans have confirmed All-Australian goal-sneak Stengle fractured his left arm and ruckman Stanley fractured his right eye socket during Sunday's win over West Coast.
Both will undergo surgery this week, with the club expecting them to be sidelined "for the medium term".
"There's not a team out there that won't have to endure these issues," Cats coach Chris Scott said after Sunday's 47-point victory.
"It's part of the trick, I guess, over a long season where the competition is just so even and every game is potentially really challenging, the depth of your squad becomes a really important factor."
After starting the season 0-3, Geelong have bounced back with convincing victories over Hawthorn and the Eagles.
They host Sydney at GMHBA Stadium on Saturday night in the two sides' first meeting since last year's grand final.