Geelong midfielder Max Holmes will be out for the medium term after undergoing knee surgery, while prized draft pick Jhye Clark has been cut down by a serious foot injury.
Holmes tore the meniscus in his right knee during last week's loss to Fremantle in Perth.
The 20-year-old underwent surgery on Tuesday and won't be available until after the club's mid-season bye.
"Max had been in great form and was really building his game in the early part of the season, so he'll spend a couple of weeks where he won't do much and then it'll really ramp up after that," Geelong general manager Simon Lloyd told the club's website.
Clark, the No.8 pick from last year's national draft, has been diagnosed with a navicular stress reaction in his foot.
No timeline has been set for his return.
Clark made his AFL debut in the round-nine loss to Richmond, but he missed last Saturday's defeat to Fremantle after reporting soreness earlier in the week.
"Pretty soon he'll start to weight bare and again," Lloyd said.
"Particularly with the young players we need to think long term so we'll be more conservative."
In better news for the Cats, Ollie Henry (ruptured testicle), Sam De Koning (facial fracture) and Gary Rohan (hamstring) could all be available for Saturday's home clash with GWS.
Brisbane are set to regain veteran Daniel Rich for Sunday's match against Adelaide, but in-form defender Jack Payne will miss with concussion.
Rich has missed the past three weeks after injuring his calf in the round-seven win over Fremantle, but he completed full training on Tuesday to prove he is ready for a recall.
Richmond defender Nick Vlastuin is still hopeful of playing in Sunday's encounter with Port Adelaide at the MCG despite suffering a corked leg in last week's Dreamtime loss to Essendon.
St Kilda's Mitch Owens will miss at least a week with concussion after colliding with the knee of teammate Anthony Caminiti in Sunday's win against the Giants.
But forward Tim Membrey is a chance to return from concussion in Saturday's match against Hawthorn.
Hawthorn are hopeful to have ruckman Ned Reeves available.
Reeves was subbed out in the third quarter of last week's win over West Coast with an ankle injury, but he has recovered well from the injury.
"Ned had an incident during the game with his ankle, different to the mid-foot sprain that we were dealing with two weeks ago, so separate incident," Hawthorn high performance manager Peter Burge said.
"The great news is that he has pulled up really well and he was running today in straight lines with his runners and we anticipate he is going to resume training with the main group on Thursday."
Gold Coast defender Sean Lemmens will miss about four weeks with a hamstring injury.
