Boston Bruins center Patrice Bergeron left Tuesday's game against the Ottawa Senators with 7:44 elapsed in the second period, and the team announced he would not return. Bergeron's head collided with Colin Greening's elbow or forearm as the Boston center tried to prevent the Greening from getting off a shot in the slot. Bergeron, last season's Selke Trophy winner as the NHL's top defensive forward, began the night with a team-high 31 points. In his career, Bergeron has accumulated three high-profile concussions, starting with one in 2007 that forced him to miss two-thirds of the regular season and Stanley Cup Playoffs