William Nylander's concussion suffered at the world juniors may have cost him more than the remainder of the tournament.

Sportsnet's Damien Cox reported Saturday on Hockey Night in Canada's "Headlines" segment that Nylander may not get to join the Toronto Maple Leafs after the All-Star break - an opportunity the organization was apparently preparing.

"That's all off the table right now," Cox said. "I think he's going to miss a month or more when it's all said and done."

Nylander apparently returned to Toronto on Wednesday and has embarked on his return-to-play concussion protocol.

The former eighth overall pick was first in American Hockey League scoring at the time of his departure (he now ranks second) for the world junior tournament.

Nylander was knocked out of the competition on his second shift as a result of a blindside hit from Switzerland's Chris Egli.