Prized Fremantle recruit Luke Jackson will miss Thursday's pre-season match against Port Adelaide due to a head knock, while veteran Michael Walters faces a race against time to be fit for Round 1.
Jackson suffered a hit to the head in last week's practice match loss to Adelaide.
The 21-year-old impressed up forward and in the ruck during that hit-out, and coach Justin Longmuir is confident Jackson will be fit to return for the round one clash with St Kilda on March 19.
"Luke Jackson got a knock in a contest and had a bit of delayed headaches from that, so we'll rule him out this week," Longmuir said on Monday.
"It's a no-risk policy around head knocks so we'll not play him this week but he should be right come round one."
Both Michael Frederick (quad) and Walters (Achilles) will also miss this week's match against Port.
Walters is no certainty to face the Saints in round one.
"He's tracking really well, and we're still fingers crossed he'll be right for round one. But we're not going to rush him," Longmuir said.
"We need to make sure that once he comes back, he's ready to play out the whole season."
Defender Luke Ryan (back) is another player who will sit out this week's action, but the Dockers will welcome back Nathan O'Driscoll (foot hot spot) and Heath Chapman (tight hamstring).
Port are set to be boosted by the return of Charlie Dixon, Zak Butters and Darcy Byrne-Jones, but veteran Travis Boak is unlikely to play after being injured in a collision with Jeremy McGovern last week.
Scans cleared Boak of a fracture but showed extensive bruising around the ribs and lungs.
Although Fremantle lost the scratch match to Adelaide by 11 points, there were plenty of positives to come out of it - most notably the three-goal haul by former midfielder Nat Fyfe.
The two-time Brownlow medallist was hampered by injuries in 2022, but could be set for a huge year up forward, with a full pre-season under his belt.
Relinquishing the captaincy to Alex Pearce also looks to have taken a weight off Fyfe's shoulders.
"I thought he got better as the game went on," Longmuir said of Fyfe.
"Not only did he get on the end of a few opportunities, he created a few opportunities.
"He got more and more confident in his game as the game went on. He got a bit of his old mojo back. It was good."
Longmuir praised the pre-season campaign of Ethan Hughes, who looks to have locked in a round-one berth for himself either at half-back or on the wing.
With Jackson absent this week, young forwards Jye Amiss and Josh Treacy are expected to get another chance to push their case for a round-one spot.