Josh Treacy is set to miss a second straight week with a knee injury as Fremantle take a cautious approach with their star forward.
Treacy missed last Saturday's 11-point loss to Geelong after suffering a minor PCL injury in the one-point loss to Essendon the previous week.
The Dockers were initially hopeful Treacy would be ready to return for Saturday's crunch clash with the Giants at Engie Stadium, but coach Justin Longmuir confirmed the 22-year-old was almost certain to miss.
"More unlikely than likely," Longmuir told reporters on Wednesday.
"It's improving, but you just can't take a risk on it. Chances are he'll miss another week.
"It's clearly a week-by-week injury. I thought he was a good chance to get up last week.
"We were hoping he'd get up this week as well, but it hasn't improved as quickly as we needed.
"We can't take any risks with him, we've just got to get it right."
Longmuir has already ruled out skipper Alex Pearce (broken forearm) until the start of the finals.
And ruckman Sean Darcy, who was a late withdrawal last week due to knee soreness, will have to manage the injury for the rest of the year.
Darcy is a chance to face the Giants if he can pass a series of fitness tests this week, while Michael Walters (hamstring) is a strong chance to return.
Tight losses to Essendon and Geelong have put Fremantle's AFL finals hopes on thin ice.
The Dockers (12-8-1) sit sixth, but the Western Bulldogs, Hawthorn and Carlton are only half a win behind them and have the luxury of much easier draws to finish the regular season.
Fremantle face GWS at Engie Stadium on Saturday, before rounding out the regular season at home to high-flying Port Adelaide.
GWS (14-7) have soared into third spot on the back of six straight wins.
Former Dockers forward Jesse Hogan has been crucial to the Giants' revival, kicking 25 goals over the past six games.
"Get the right match-up, stop his supply," Longmir said when asked about the challenge of curbing Hogan.
"He's been in phenomenal form, taking lots of contested marks, he's kicking really accurately, getting some good supply."
GWS are expected to welcome back vice-captain Stephen Coniglio (shoulder) and ruckman Kieren Briggs (managed).
