The game, which ended 52 minutes, eight seconds into overtime, was the fifth-longest Stanley Cup finals game in NHL history. The longest lasted 55:13 of overtime in 1990 between the Bruins and the Edmonton Oilers.
“It was a great battle for us,” Shaw said in a televised interview.
The Blackhawks host Game 2 in the best-of-seven series on June 15.
Michael Rozsival shot from the right point into a crowd in front of the net at United Center in Chicago. The puck deflected off Dave Bolland and then Shaw before slipping past Boston goalie Tuukka Rask at 12:08 of triple overtime.
“He’s a competitor, he does things game in, game out,” Blackhawks coach Joel Quenneville said of Shaw in a news conference. “The bigger the stage, the bigger the challenge, he rises to the occasion. He knows where the front of the net is. He’s relentless.”
Boston’s Milan Lucic scored goals in the first and second periods before Brandon Saad gave the Blackhawks their first score 3:08 into the second period.
Patrice Bergeron had a power-play goal in the third as the Bruins took a 3-1 lead. Bolland scored at the eight-minute mark and Johnny Oduya tied the game 3-3 four minutes later to force the overtime.
Nathan Horton, the second-leading scorer for the Bruins, was injured in the first overtime and left the ice. He didn’t return for the remainder of the game.
Corey Crawford stopped 51 shots for the Blackhawks, while Rask had 59 saves for the Bruins.
Bruins coach Claude Julien, whose team won the Stanley Cup in 2011, said in a news conference that he didn’t consider the loss devastating.
“Last time we won the Cup, we lost the first two games to Vancouver; it never stopped us from coming back,” Julien said. “This certainly won’t. They got a good break on their tying goal going off one of our skates. That’s the way the game goes. Some nights you get the break going your way, some nights you don’t.”
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