Fremantle fears Brownlow medallist Nat Fyfe has re-injured the leg he broke during last season's preliminary final.
Fyfe sat out the second half of Sunday's loss to Carlton on the bench with a large ice pack strapped to the lower part of the leg he fractured during last season's preliminary final.
He limped onto the ground to commiserate with his beaten teammates after the Blues' four-point win.
Fremantle coach Ross Lyon said the Fremantle Dockers won't know the extent of the problem until Fyfe has scans within the next 24 hours.
Lyon post-match Q & A
"We're really concerned in relation to where he's got his plate in his broken leg," Lyon said after the match.
"I'm not sure, I think it was a severe kick to the leg. I don't even know how it happened.
"Once the investigations are done and I'm sure that will be within 24 hours I would imagine the club would do a press release and keep everyone updated."
A serious injury to the superstar midfielder would be a blow to the Fremantle Dockers after an 0-5 start to the season.
Fyfe played out the Fremantle Dockers' 2015 preliminary final loss to Hawthorn despite fracturing the fibula in his left leg.
He attended the Brownlow Medal presentation walking with a cane, before undergoing surgery.
Fyfe might not be the only casualty from the loss to Carlton. Hayden Ballantyne copped a heavy cork to his thigh in the first term and he struggled to run thereafter despite playing out the game.
Michael Johnson twisted his right knee in the action of kicking during the thrilling final term. He told AFL.com.au that he wasn't sure what the problem was post-match.
"It's a bit stiff," Johnson said.
"It was just in the action of kicking but I haven't had the push and feel from the physios after the game yet. I was happy to go back on and try and play out the game. We'll just see."
Lyon said the club doctors were unsure what the issue was after an initial assessment on the boundary line.
Lachie Neale had a bandage on his calf while Lee Spurr suffered a cut above his eye. But Lyon refused to use any of the injuries as a reason for the loss to the Blues.
"It was difficult but it's no excuse," Lyon said.
Freo lacking composure
"Good teams get it done and great teams don't even worry about it. So Ballantyne had a severe cork and head knock. Johnson was later in the game. But they're excuses. We still had opportunities to win that game. But if you play and move the ball like we're playing we're not going to beat too many."
The Fremantle Dockers are already without Aaron Sandilands for an extended period with a rib and lung injury and star recruit Harley Bennell won't be seen until the second half of the season with a calf problem.
Skipper David Mundy looks set to return next week to face Adelaide next week after missing the last three matches with a calf injury.
Lyon said he was likely to come straight back in and also said that youngsters Connor Blakely and Ethan Hughes were a chance to get an opportunity next week along with experienced duo Matt de Boer and Tendai Mzungu after good performances for Peel Thunder on Saturday.
