Fremantle clinched a top-four spot for the AFL finals but Sunday's 95-point win over Melbourne came at a heavy cost with ruckman Aaron Sandilands suffering a suspected fractured cheekbone.
Fremantle's 20.13 (133) to 5.8 (38) victory keeps the Dockers (62 premiership points) only half a win away from second-placed Geelong with two rounds remaining.
However Sandilands is likely to miss the next two games while small forward Hayden Ballantyne, who suffered a shoulder injury, is also facing an interrupted preparation for September.
Fremantle coach Ross Lyon said Sandilands had been taken to hospital for a scan after his head knock and might have to travel by road back to Perth.
"It doesn't look great," Lyon said.
"It looks like a cheekbone (fracture).
"We know you can play with them. Potentially he (Sandilands) could miss one or two (weeks) but he'll certainly be available when the whips are cracking so that is really positive."
Sunday's round-21 clash, which at times was little more than a training run for the Dockers, attracted a tiny crowd of 13,768 fans at the MCG.
Ballantyne and skipper Matthew Pavlich booted four goals each for Fremantle while David Mundy dominated midfield and athletic big man Zac Clarke was also influential.
Nineteen-year-old hard nut Jack Viney was one of Melbourne's better contributors as the Demons suffered their 18th loss from 20 games.
Melbourne's 103kg defender Jake Spencer ran with his back to the ball and crashed his forearm into Sandilands' head during a marking contest early in the first term in an incident which will be assessed on Monday by the match review panel.
The 211cm Sandilands left the field looking groggy as blood streamed from a gash on his swollen forehead.
Fremantle led by 27 points at quarter-time after holding the Demons goal-less in the opening term.
The Demons trailed by 31 points at halftime after kicking four goals to Fremantle's five, but it was one-way traffic after that with the Dockers scoring 11 goals to one.
"It was a professional performance, bank four points and what is really important about that is that we have locked up our top-four position now," Lyon said.
"From here it is two weeks to improve our football.
"(With) other results potentially (Fremantle can) go higher but for the moment that will suffice, a double chance."
Fremantle host eighth-placed Port Adelaide next Saturday.
Melbourne coach Neil Craig said he hoped to regain defender James Frawley and key forward Chris Dawes for next Saturday's AAMI Stadium clash with Adelaide.
Shannon Byrnes (foot), Sam Blease (ankle) and James Strauss (shoulder) are all in doubt.
"No one likes close to a 100-point loss, but for our team to play against Freo, who are in really good shape, you can't buy that experience," Craig said.
