Reason for William Nylander’s playoff absence hard to pin down
Elliotte Friedman reports on the ailment that has kept Toronto Maple Leafs winger William Nylander out of the lineup for the first three playoff games.

Elliotte Friedman explains that William Nylander has a severe migraine, but there isn't certainty, at least in what he can report, as to if that's from an injury.

Given this, you should expect what you've been seeing so far: Nylander participating to some extent in practices and skates, but not being in the lineup for sure.