Port Adelaide defender Jake Pasini will miss the remainder of the 2022 season after rupturing his left anterior cruciate ligament at training on Tuesday.
It is understood the 21-year-old landed awkwardly during a marking contest.
Power medical expert Tim O'Leary expressed his sympathy for Pasini but backed the youngster's persistence, referencing a 2021 shoulder setback.
"It is really unfortunate for Jake given his recent form and the consistency he has been developing in his game," O'Leary said on Tuesday.
"He has had some challenges as a young player already, but we saw how hard he worked coming back from a shoulder reconstruction early last year and I have no doubt he will attack his rehabilitation with the same positivity and application."
The Swan Districts product averaged 16.7 disposals, 4.5 marks and 3.2 tackles across six SANFL games this season before the injury.
Pasini was taken by the Power with the eighth selection of the 2019 Rookie Draft but is yet to make his AFL debut.
