Young Port Adelaide midfielder Jake Patmore will be unlikely to feature at any level this year after tearing his anterior cruciate ligament.
The 20-year-old landed awkwardly in a SANFL trial game between Port Adelaide and South Adelaide on Friday.
Scans on Saturday revealed the severity of the injury.
“This is a terrible blow for Jake, who had been developing well after his second pre-season,” Port Adelaide's general manager of football Chris Davies said.
“But we know he is a resilient young man and everyone at the club will support him through his rehabilitation.”
Patmore is yet to make his debut for Port Adelaide after being drafted with pick 58 in the 2017 AFL draft.
He played every game for Port Adelaide in the SANFL in 2018, kicking 16 goals from his 18 games.