It’s not every night that you’ll see an NHL game in which a team has a five-goal lead before the contest is half over, wins by four, but its goalie has to be its best player. So even when the Bruins showed some rare offensive flare, it was not the best indication as the playoffs approach that Tuukka Rask (40 saves) had to be great early and pretty good all the way through in last night’s 6-2 win against the fading Carolina Hurricanes. How great? Well, Rask somehow shot out his left pad to stone Hurricanes center Zac Dalpe on a clean 2-on-0 break when the game was still scoreless in the early minutes. That may have been his best save — it may have been the B’s save of the year — but he also made a bundle of other good ones. Bruins coach Claude Julien talked about the fine play and finish in the offensive zone, which had been lacking. What also has been missing is a complete, 60-minute performance, the sort of game so common in the Stanley Cup run two years ago that we haven’t seen much of this season, and the B’s don’t have much time to find it. “In the offensive zone we did a pretty good job,” said Julien. “Now it’s a matter of combining both (with) better defensive play. I didn’t think we were very good in that area. We’re not at our best defensively. “(Carolina) is a team that will expose you even more with their aggressive forecheck, having all five guys right on top of you. It exposed us a little bit, no doubt about that. We’ve got to get better in that area.