Fremantle captain Nat Fyfe is facing a race against time to be fit for Saturday night's western derby after copping the worst concussion of his glittering AFL career.
Fyfe was knocked unconscious after clashing heads with Josh Battle in Fremantle's five-point victory over St Kilda on Sunday.
The Brownlow medal winner couldn't even stand up by himself when he tried to get up off the ground, with his legs like jelly as the trainers carried him off.
The six-day break between games reduces Fyfe's chances of proving his fitness for the crucial match against West Coast.
Fyfe will have to go through a series of physical and mental tests during the week before a decision is made on his availability.
Fremantle coach Ross Lyon praised Fyfe's bravery.
"I knew he'd be unflinching," Lyon said.
"He gets a lot of treatment every week but he never complains. He kept his eye on the ball and he sets a great standards.
"As you'd suspect he's a little bit doey, but he's pretty good."
Richmond captain Trent Cotchin appears set to miss Saturday's crunch clash with Port Adelaide after injuring his hamstring in the loss to GWS.
Cotchin came off in the third quarter with the injury, while Jayden Short injured his elbow.
The setbacks come at a bad time for the struggling Tigers, who are already without Alex Rance (knee reconstruction), Jack Riewoldt (wrist) and Bachar Houli (hamstring).
Dustin Martin could also be ruled out against the Power if he is suspended for his off-the-ball hit on a Giants player.
Adelaide were left breathing a huge sigh of relief when wingman Paul Seedsman avoided an ACL knee injury.
The Crows were fearing the worst when Seedsman went down in the loss to Geelong, but scans cleared him of ACL damage.
It remains unclear how long Seedsman will be sidelined for.
Carlton are sweating on Mitch McGovern's hamstring injury, while Hawthorn's Jarryd Roughead (thigh), Port Adelaide's Tom Rockliff (concussion), Giants recruit Tommy Sheridan (calf), and Geelong's Tim Kelly (ankle) are other players who have injury concerns.
Sydney duo Will Hayward (broken jaw) and Jarryd McVeigh (quad) appear set for significant stints on the sideline.
