Nicklas Backstrom scored 2:56 into the second overtime period to earn the Capitals a 2-1 victory at Boston and even their series at one win apiece. It was the second playoff overtime goal of Backstrom's NHL career; he scored an OT winner at Montreal in Game 2 of Washington's first-round series against the Canadiens in 2010. Backstrom's two playoff overtime goals tie a Capitals team record he now shares with Dino Ciccarelli and Joe Juneau. - Elias Sports Bureau, via ESPN
Here are Backstrom's two:
Juneau's first is at 0:45 and of this clip...
... and his second is right here:
Ciccarelli's two came on April 5, 1990 (at New Jersey) and April 11, 1991 (at the Rangers).