Nat Fyfe will miss Fremantle's clash with Carlton next week after being heavily concussed in his team's 31-point win over Greater Western Sydney on Sunday.
The Dockers captain was left dazed and confused after copping a high bump from Sam Reid late in the third quarter of the 11.21 (87) to 7.14 (56) win at Optus Stadium.
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The two-time Brownlow medallist was watching the ball after his teammate dropped a mark when Reid collected him with sickening force.
Fyfe, who had tallied 1.2 from 15 disposals playing as a permanent forward, was helped off the field by trainers before being subbed out of the game.
The incident is sure to be looked at by match review officer Michael Christian, given the serious and high impact of the bump when not in possession of the ball.
Fans flocked to social media to condemn Reid and call for a big suspension.
Dockers received timely boost with Fyfe out
Fyfe has a history of concussion, and has gone on record to say it is an injury that he is acutely aware of given its potential long-term effects.
Dockers coach Justin Longmuir said he wasn't sure when Fyfe would return, but the skipper will miss at least the Carlton game on Sunday due to the AFL's 12-day protocol for all concussions.
"He's good in the change rooms now, he's up and about," Longmuir said.
"He's getting around his teammates. We subbed him out of the game. What that means for the next couple of weeks, I'm not sure.
"We tread carefully with all concussions, and he won't be passed fit to play before he ticks every box with our doctors. That's the same with every player."
Fremantle's battered forward line is set to receive a timely boost, with both Michael Walters and Josh Treacy in line to play against Carlton.
Walters hasn't played since injuring his hamstring in a pre-season match against West Coast, but Longmuir expects the 30-year-old to be given the green light to return this week.
"He's ticked most boxes," Longmuir said.
"The way I saw him running out here (on Saturday) - I don't want to declare him fit, I'll let the medical staff do that.
"But he doesn't have to do a lot I wouldn't have thought, except get through main training."
Treacy was pencilled in to make his AFL debut in round one against Melbourne, but those plans were scuppered when the key forward copped a two-match ban from a WAFL practice game.
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