North Melbourne youngster Ed Vickers-Willis will not play again this season.
The promising 21-year-old, who made his debut in round five this season, played seven games in a row this year before suffering a knee injury in Round 11.
He has missed the past six weeks due to a PCL injury and was initially expected to return towards the end of the season.
However, the club has taken a cautious approach and will not risk him for the remainder of the year.
"The focus for Ed will now be on building the strength back in his knee in preparation for the pre-season campaign," football manager Cameron Joyce said.
"Ed has been tracking well in his recovery and there's been no set-back, we're simply taking a long-term approach to allow him more time to fully recover and put himself in the best position ahead of the 2018 season."
The Roos face Essendon at Etihad Stadium this Saturday afternoon.