Fremantle will await scans on a fresh hamstring injury to star midfielder Hayden Young, who was subbed out of Friday's 10-goal loss to St Kilda.
Young came from the field in the second term of the Round 8 affair after a tackle attempt that left him in pain near the boundary line.
He was assisted from the field and soon ruled out of returning, with Young's hamstring put on ice.
The ailment is the third of its kind for Young this year, all of which have come on his right hamstring, with a setback in late February seeing Young sidelined until Round 5.
A moderate hamstring strain would see Young facing close to three weeks out of action, while a high-grade strain often results in approximately six weeks on the sidelines.
Coach Justin Longmuir revealed post-game that the concern for Young looked "serious".
"We'll get it scanned, but it doesn't look great," Longmuir said.
"It looks serious."
The Dockers' midfield is already without Jaeger O'Meara (hamstring/foot), Nathan O'Driscoll (ankle) and Nat Fyfe (hamstring), while Michael Walters (knee), Brandon Walker (shoulder) and Sam Sturt (knee) are also occupying the club's casualty ward.
Fremantle, who have slid to a record of 4-4 in the wake of their latest loss, face Collingwood, GWS, Port Adelaide and Gold Coast in the next four rounds before their mid-season bye.
