The Panthers have lost six of their last eight games.
Marchand’s second goal made it 3-0 at 9:40 of the second. Torey Krug‘s power-play shot from the high slot was blocked, but Marchand swept in the rebound.
Marchand, who leads Boston with 12 goals and 34 points, also had a short-handed goal at 12:48 of the first. He grabbed the puck from Panthers defenseman Keith Yandle, skated in, and backhanded the puck between Reimer’s glove and the post.
The Bruins went ahead 2-0 when Backes tipped in a shot from David Krejci at 4:13 of the second. Backes missed the previous three games with a concussion.
Nash poked in the puck off Reimer’s body and into the net at 4:59 of the third.
NOTES: Panthers F Greg McKegg left in the second period with an upper-body injury. … Florida C Nick Bjugstad will miss two weeks with a lower-body injury. … Panthers D Aaron Ekblad played in his 200th NHL game. … The Panthers recalled goaltender Sam Brittain from the Manchester Monarchs of the ECHL to back up Reimer. … The Bruins recalled Zane McIntyre from Providence of the AHL to back up Rask. McIntyre has played in three games this season (0-2-0).
Bruins: Visit Carolina on Sunday.
Panthers: Visit New Jersey on Monday.