Toronto Maple Leafs team doctors pulled Auston Matthews from Game 4 during the second intermission because of an illness, head coach Sheldon Keefe said postgame.
Matthews played the first 40 minutes of the contest but didn't return for the start of the final frame. The Maple Leafs trailed the Boston Bruins 3-0 after two periods and ultimately lost the game 3-1, falling behind 3-1 in the series.
The 26-year-old played through the illness in Game 3 and missed Friday's practice.
"It's not one of those run-of-the-mill everyday type of illnesses that come and go," Keefe said Sunday, according to Chris Johnston of Sportsnet. "This one has lingered. The effects have lingered and gotten worse when he gets on the ice and is asserting himself."
Matthews produced a dominant three-point effort in Toronto's Game 2 win but has otherwise been held off the scoresheet in Round 1.
Matthews won the Maurice "Rocket" Richard Trophy for the third time in four years this past season, leading the league with 69 goals.
