It’s not often that a goaltender steals the show in a 5-2 playoff victory. But that was the case last night as the Bruins took a 2-1 lead in their best-of-seven first-round series against the Toronto Maple Leafs. While the Bruins had a pretty good offensive assault, throwing 38 shots at the Leafs’ James Reimer, they might be regretting things today if it hadn’t been for Tuukka Rask. The Finnish netminder weathered a 47-shot barrage at a raucous Air Canada Centre, 18 of them coming in the third period as the Bruins appeared overwhelmed with the task of protecting a 4-1 lead. With Leafs buzzing around the net and taking advantage of sloppy turnovers, Rask held the home team to one third-period goal, on a power play, that no goaltender could have stopped. “He played huge for us,” said winger Milan Lucic, who had a big night of his own with three assists and a trio of big hits. “He played well and made the stops when he needed to,” said Toronto coach Randy Carlyle. Rask made his biggest save early in the second period when he stopped Joffrey Lupul in close to preserve a 1-0 B’s lead. Less than a minute later, Rich Peverley scored to make it 2-0. Rask agreed that might have been the turning point in the game. “It was a one-goal game at that point, so it was pretty important,” he said. “It was just kind of one of those knuckleballs and it just dropped and missed my glove and I just kicked my pad out.” Though he couldn’t be faulted on either of the Toronto goals, Rask admitted luck played a role. Two shots got past him but clanged harmlessly off the goalposts.