Newly acquired forward Brett Connolly suffered an injury on just his second practice with the team.
Connolly suffered a displaced fracture in his right index finger and will be out for six weeks.
It happened after taking a shot from Bruins defensemen Dennis Seidenberg.
The Bruins traded two second-round draft picks for Connolly.
Connolly was expected to be at the TD Garden on Thursday against the Calgary Flames to make his debut with the team.