The Stanley Cup finals between the Bruins and Chicago Blackhawks has been a roller-coaster ride of a series. Last night, one Bruin was launched up in a rocket — up the depth chart, that is. Carl Soderberg not only went from a perennial healthy scratch to making his Stanley Cup playoffs debut in the B’s 3-1 loss in Game 5 that left them trailing in the series 3-2, by the third period he was the team’s No. 2 center, skating between Brad Marchand and Jaromir Jagr after Patrice Bergeron had to leave the game with an undisclosed injury. It took the 27-year-old just one shift to make his presence felt, as Soderberg stole the puck from the Blackhawks’ Andrew Shaw at the red line and landed two shots on goalie Corey Crawford before the next stoppage of play. “Yeah, that was nice to get a couple shifts right away so you get into the game,” Soderberg said. “So then I played a lot in the second and third period. But unfortunately we didn’t win. So now we have to win two straight games and we have to go back to Boston and play like the third period tonight. So we played really great in the third period. I don’t know if the first and second was that good.” Soderberg didn’t land any more shots on Crawford, but he did finish with three hits and filled in admirably for Bergeron despite his line’s inability to produce the tying goal. Although he hadn’t played a game since April 28, coach Claude Julien told one national media member that he’d been considering inserting the Swedish import for about a week. On Friday, Julien skated Soderberg, who had two assists and a minus-2 rating in six regular-season games, with Rich Peverley and Shawn Thornton instead of Kaspars Daugavins in practice. As of the team’s morning skate yesterday, Julien said he was still weighing the decision between Soderberg and Daugavins, who had been in the lineup ever since Gregory Campbell’s season was ended by a broken leg in Game 3 of the Eastern Conference finals.