After Toronto scored two quick goals early in the third period to take a 4-1 lead, Boston battled back, getting goals from Nathan Horton, Milan Lucic, and finally Patrice Bergeron with less than a minute remaining to tie the game and force overtime.
And then at 6:05 of the first overtime period, Bergeron would score again to win it:
The Boston Bruins will move on to face the winner of the Capitals-Rangers series in the East.
Let's take a look at the big questions we were tracking in this game:
Who has gas left in the tank?
The Bruins dictated the first few minutes of the game before the Maple Leafs took over for most of regulation. Boston appeared tired and slow for much of the night, but found an extra gear when it mattered.
Will Tyler Bozak play and win draws?
Bozak was out of the lineup again, and the Maple Leafs were dominated in the face-off circle in the game.
Can the Bruins get anything from their fourth line?
The fourth line remained scoreless for Boston, but they didn't need secondary scoring to win the game. Their big stars came to play.