In his post-game press conference, the coach stated that Matthews had to leave the ice due to his ongoing illness, the same issue that forced him to miss a few practices this week.
They made a great effort, but the Bruins' goalie Jeremy Swayman, as well as their defensive unit, did an amazing job at holding the Leafs back. As for the forwards, they were opportunistic and capitalized on the small mistakes, just like they did all series long.
The Leafs will try to avoid the elimination tomorrow, in Boston. As for Auston Matthews, it's hard to predict what'll happen to him. If he's not healthy enough to play, it's hard to imagine a scenario where the Bruins don't reach the second round.