Richmond youngster Nathan Drummond has been helped off with an injury in the VFL, with the club reportedly suspecting he has torn his anterior cruciate ligament.
Drummond was helped off the field by trainers during Richmond's VFL clash with Sandringham.
Fairfax Media reported the club believes it is a second torn ACL for the 22-year-old.
He tore the ACL in his other leg on his AFL debut in 2015 against Melbourne.
He made his return to footy midway through 2016, playing in the VFL and finishing the year with four more AFL games.
Drummond was grabbed by the Tigers with pick 52 in the 2014 AFL draft.