Donato, who was called up from Providence of the American Hockey League on Wednesday, scored the only goal of the shootout on a backhand shot past goalie Robin Lehner after a deke to his forehand side. He's 2-for-2 in his NHL career in shootouts.
"A lot of guys were trying to go five-hole on him," said Donato, who had one goal in 11 games Boston before he had nine (five goals, four assists) in 10 games for Providence. "I just knew that he would hopefully bite on the first move, and I was lucky he did and got it past his right pad."
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Tuukka Rask made 28 saves and then stopped all four Islanders in the shootout, and Brad Marchand scored for the Bruins (14-7-4), who have won four in a row at home and are 4-1-2 in their past seven games.
"I thought [Rask] got better as the game went along," Boston coach Bruce Cassidy said. "I thought none of us were sharp early. Not that we were bad, just we weren't executing to our standards, playing with the energy up to our standard. And eventually we get behind. But Tuukka was excellent. Overtime obviously is an issue for us in terms of what we give up, we're not managing pucks well, we're not reading rushes quick enough. And he made some huge saves."
Lehner made 35 saves, and Anders Lee scored for the Islanders (12-9-3), who have lost two in a row and four of their past six games.