Dual Brownlow medallist Nat Fyfe could receive an SOS call as early as this week after Fremantle confirmed Hayden Young had suffered an adductor strain.
Young tweaked his groin tackling an opponent in Fremantle's 27-point win over Carlton at Optus Stadium on Sunday.
The 24-year-old was playing just his third game back from hamstring surgery, and his groin setback leaves a massive hole in the midfield.
The Dockers confirmed on Monday Young would definitely miss Saturday night's match against Port Adelaide, with a more concrete timeline to be provided in coming days.
"We've escaped serious injury. It's just a matter of whether we can get him back before our last game," Dockers coach Justin Longmuir said on AFL 360.
"We're cutting it pretty fine with timelines. We'll get a little bit more information back and see where the timelines fit.
"Clearly the last couple of weeks has shown that he's important to us.
"He adds a different dimension to our midfield.
"Having said that, we've got to this point without him for the majority of the year, so I'm sure we'll be fine.
"I feel for him more than I feel for us. He's been in and out all year and had setbacks. He'll be flat."
Fremantle initially struggled against Carlton without Young's big body and class, with the Dockers trailing by 24 points at halftime before Jaeger O'Meara's move to the midfield to quell George Hewett helped turn the tables.
Fyfe has missed most of the season after damaging his hamstring soon after returning from knee surgery.
The 33-year-old made his belated return in round 12, before injuring his calf just three matches later while warming up at half-time as the sub.
Fyfe's latest bid to return to the AFL side began on Saturday when he racked up 27 disposals, six tackles and five clearances while playing for Peel Thunder in the WAFL.
That huge display came despite him being rested for the entire final quarter, with Fyfe now a chance to return to the AFL side for Saturday night's clash with the Power in Adelaide.
"I thought he was the best player on the ground for his 60 minutes," Longmuir said of Fyfe.
"He only played 60 minutes though, so we'll have a chat during the week.
"He'll be involved in that and work out his next progression and whether there's a spot in the side."
Asked whether Fyfe needed some continuity first, Longmuir replied: "A little bit, but we're running out of time in the season and we need to put our best team out there to win next week.
"A lot of things will come into consideration with him and Alex Pearce coming back, but we need to get going as well.
"So we'll see what it spits out at selection."
If Fyfe plays, there's a strong chance he will be the sub.
Pearce has played just one of Fremantle's past nine matches due to a hot spot in his shin, but is in line to return against Port.
Fremantle have just three more matches - against Port, Brisbane and the Bulldogs - before the finals begin, so the race is on for Young to overcome his injury and build up fitness.