Toronto Maple Leafs prospect William Nylander reportedly sustained a head injury during a game in Sweden on Saturday.
The news was first reported by James Mirtle of The Globe and Mail, followed by Swedish reporter Uffe Bodin of HockeySverige.se.
Nylander was accidentally hit in the head by a skate and may have suffered a concussion, according to Bodin.
The Maple Leafs selected Nylander with the eighth pick in June's draft. He was assigned to Swedish club Modo in early October to work on his strength.
The 18-year-old center has five goals and nine assists in 12 games with Modo this season.