Dennis Seidenberg got off a blast from the point that was tipped by Bergeron. The deflected puck made it through the pads of goaltender Robin Lehner and trickled across the goal line.
Ottawa had won five in a row and began the night tied with Boston for second place in the Northeast Division with 26 points. The Bruins, however, have played four fewer games than has Ottawa.
Tuukka Rask made 30 saves for the Bruins, who have won eight of their last 10. Lehner gave up the winning goal on the 46th shot he faced.
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