Carlton are hopeful Zac Williams will return to provide a late to boost to their AFL finals bid after scans confirmed he has a high-grade calf strain.
Williams is expected to be sidelined for the next 10-12 weeks, having sustained the injury during the opening quarter of the Blues' 30-point win over GWS on Sunday.
The result moved Michael Voss' side back into the top-four with a 6-3 record ahead of Friday night's clash with Sydney at Marvel Stadium.
On Monday, Carlton head of football Brad Lloyd indicated Williams will be eyeing a return in the latter stages of the home-and-away season.
There had been fears the dashing defender's season would be over if scans had revealed an achilles tendon injury.
"We took the time to get Zac back to Melbourne and get a scan today to assess the injury fully, which unfortunately has confirmed he will be out of the side for an extended period," Lloyd said.
"Zac is understandably disappointed given the work he's done to get himself playing good football and performing an important role as part of our back six.
"We've had a number of personnel changes over the opening nine rounds but to the players' credit they have adapted and there will be another opportunity for someone to step up and take their chance at senior level."
Williams has played all but one game this season, Voss' first at the helm.
Meanwhile, struggling Essendon have suffered another blow with young star Nik Cox likely to undergo surgery on a Lisfranc injury to his right foot.
Teammate Jye Caldwell might yet be available for Saturday's clash with Richmond despite a shoulder injury but Cox is set for a stint on the sidelines.
He will see specialists to determine his best course of action.
"We anticipate to know the extent of Nik's injury over the coming days after he meets with a foot and ankle surgeon for further determination," Essendon football manager Josh Mahoney said.
"It is likely he will be sidelined for several weeks as a result of the Lisfranc injury, which is disappointing for Nik, but we will know more in the coming days."
Western Bulldogs spearhead Aaron Naughton (knee) and speedster Jason Johannisen (calf) face fitness tests before Saturday's clash with Gold Coast in Ballarat.
Dogs ruckman Tim English will miss at least one more match through illness after spending a few days in hospital last week.
Leading goal-kicker Naughton damaged his knee during last Friday night's win over Collingwood but has avoided serious damage.
"Aaron had an incident where he over flexed and jammed his knee joint," Bulldogs head of sports medicine Chris Bell said.
"He was able to get through the game but has some expected soreness into this week.
"We are working around the clock to improve his symptoms and will make a decision on his availability after main training on Wednesday."
Australian Associated Press
Sign up for our newsletter to stay up to date.