Richmond forward Jack Higgins will stay in hospital for a second night as he undergoes tests following a brain bleed.
Higgins was admitted to hospital after he started suffering headaches.
It remains unclear what caused the problem and Tigers football manager Neil Balme told the AFL website that the brain bleed was totally unexpected.
"The feedback is that it's not terribly dangerous, but obviously it's pretty serious that it needs more tests," Balme said.
Balme and other Richmond staff have visited Higgins and report the 20-year-old is in good spirits.
Higgins has not been in their AFL team since round 13 and played in Sunday's VFL game.
Richmond are unable to say whether the brain bleed stems from any incident in that match.
They are also uncertain whether he will play again this season.
Higgins made his AFL debut last year and has played 13 senior games this season for a career total of 33.
He won the AFL's goal of the year award last season.