Key forward Ollie Lord will be sidelined for a period of time after sustaining an injury during training on Saturday.
Lord landed heavily in a marking contest, with scans showing high-grade bone bruising on the knee and an impaction fracture in the tibia.
The 22-year-old will consult a specialist in the coming days to determine whether surgery is required.
Lord will miss the start of the season, with a timeframe for return to become clear soon.