Perhaps the lasting legacy of the 2011 Stanley Cup champion Bruins was their ability to win in a hostile environment when they had no other choice. Game 7 in Vancouver was the ultimate testament to that quality. Now, these Bruins have a chance to repeat that accomplishment, and must, if they are to achieve their ultimate goal. Already, the Bruins have proven they can win in Chicago. But after losing Game 4 in overtime, they must find a way again. “It’s tough, but we know we can do it,” captain Zdeno Chara said Friday. “We have a good enough team. We just have to be ready. It’s going to be a battle.” “I guess it helps some kind of confidence there, but it’s still going to be a tough one,” Tuukka Rask said of winning Game 2 last Saturday. Chara knows the value of the experience of Game 7 in 2011 – and Game 2 this year – in Boston’s quest.