Tyler Seguin can barely grow the customary playoff beard. It's fuzzy and spotty, sort of like his rookie season. He was merely an infant the last time the Bruins played in the Eastern Conference finals in 1992, his uniform number (19) matching his age. Yet the takeaway from last night's 5-2 loss to the Tampa Bay Lightning in Game 1 is that the kid is going to be all right. If you're looking for sunny-side-up spin on what was a thoroughly disheartening evening of hockey at TD Garden, it was the play of Seguin, who looked every bit the part of a potential franchise forward of the future, collecting a goal and an assist in his playoff debut. "He had a good game,'' said coach Claude Julien, who couldn't say that about many of his charges. "I thought when he had his chance he took advantage of it and scored, and obviously he had a lot of energy tonight. So, he was a good player for us.''