The Bruins have no one to blame but themselves, and if they don’t figure it out quickly — in less than 24 hours — their season will be over. The B’s played an inexplicably ugly game Sunday night in Game 6 against the Maple Leafs, and Toronto took full advantage of it. The Leafs won the do-or-die affair 2-1, and they have forced Game 7 on Monday night back in Boston. Bruins fans have all the right in the world to be frustrated after the team’s latest disappointment, but then again, they probably shouldn’t be surprised, either. This has been the modus operandi of the B’s all season long — some nights they’re really good. Other nights, they can’t seem to get out of their own way. Game 6 was a perfect example of that. After a season in which the Bruins would be up and down from game to game, the B’s appeared to be up and down through three periods of play in Toronto. Boston played a strong first period in which they limited the Maple Leafs’ chances. They didn’t get much going offensively, but their defensive system was working and they slowed Toronto in what was a wild environment to begin the game. They got physical in the second period, where they matched the Leafs’ speed up and down the ice. Things fell apart in the third period when Dion Phaneuf scored 1:48 into the third, and Phil Kessel followed that up 7:11 later. From there, the Bruins became increasingly sloppy and really inspired no hope for a comeback. Sure enough, they fell short, despite a desperation goal from Milan Lucic in the final minute.