Dennis Seidenberg , Andrew Ference  and Wade Redden all were missing from the Bruins’ morning skate prior to Thursday’s opening game of the Eastern Conference semifinals against the Rangers. Furthermore, left wing Brad Marchand  left the ice in pain about 20 minutes into the skate following 2-on-1 drills.
With the trio of defensemen absent (all with undisclosed injuries), the lineup looked as follows prior to Marchand’s exit:
Milan Lucic  – David Krejci  – Nathan Horton 
Brad Marchand  – Patrice Bergeron  – Jaromir Jagr
Rich Peverley  – Chris Kelly  – Tyler Seguin 
Daniel Paille  – Gregory Campbell  – Shawn Thornton 
Extra forwards: Kaspars Daugavins, Jay Pandolfo, Carl Soderberg
Extra defenseman: Aaron Johnson
If Marchand is unable to play Thursday, Daugavins would be the most likely choice to replace him in the lineup. Daugavins last played in Game 1 of the Eastern Conference quarterfinals against the Maple Leafs.
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Mike Petraglia contributed to this report.