West Coast skipper Luke Shuey has been sent for scans on a leg after injuring himself at training on Wednesday.
Shuey came off the field at Mineral Resources Park shortly after the club started a match simulation session.
The 31-year-old has been plagued by hamstring and calf injuries over the past two years, and the club will be nervously awaiting the results of scans.
Shuey was expected to be nominated as captain for a third straight year, but just last week said he would consider relinquishing the role if he endured an injury-marred 2022.
"You do need your captain out there playing, ideally," Shuey, who managed just seven games last year, said.
"If this was this time next year and I had another season where I hadn't played too much footy, it (handing over the captaincy) would definitely be something I'd consider.
"But at the moment I've still got to be confident I'm going to get my body right and be able to play a lot of footy this year."
Shuey's injury comes on the back of Jack Darling being forced to stay away from the club after failing to meet the AFL's vaccine deadline last week.
West Coast released a statement saying Darling hadn't adhered to the AFL's COVID-19 training and playing mandates.
But in a bizarre twist, Darling released his own post contradicting West Coast's statement.
"The reason for my absence today was due to doctor's orders," Darling posted.
"My club has been provided with a medical certificate.
"I have been diagnosed with suffering from a work-related injury and as a result I am on sick leave until further notice.
"I will not go into any details as to my medical condition as I wish to keep that strictly private.
"I am doing my best to work with the club and my doctors so I can recover from my injury.
"I intend to return back to training as soon as I am fit and able."
