Fremantle rookie squad member Matthew Taberner will miss the start of the season after being hit by a bout of glandular fever.
Dockers coach Ross Lyon revealed the 19-year-old, recruited from the Murray Bushangers, could be sidelined by up to eight weeks with the illness.
It is a blow for the key forward who was hoping to get some exposure to AFL level during the NAB Cup, which starts for Fremantle on Saturday in clashes with West Coast and Geelong.
The Dockers will also be without senior players David Mundy (ankle), Zac Clarke (groin) and rested duo Ryan Crowley and Nat Fyfe.
However, the Fremantle brains trust was confident the quartet would be available for duty next week.
Mundy rolled an ankle at training last month and the Dockers are taking a cautious approach to his recovery because of his history with similar complaints.
Fyfe is still adding bulk to his frame and Fremantle are hopeful he can get to around 89kg, up 5kg, before the start of the home and away rounds.
Clarke tweaked a groin last week but the problem is not expected to keep him out of round one of the season proper.