Coach Bruce Cassidy said Matt Grzelcyk will be a game-time decision and will skate for pre-game warmups.
If he's unable to play, Connor Clifton will round out the defense corps.
Cassidy noted that Grzelcyk is close to a return and expects him to return on Thursday, if he does not tonight.
Grzelcyk missed Saturday’s contest with an injury, while Clifton played on the left side with Brandon Carlo.
The Bruins are anticipated to line up as follows, assuming no Grzelcyk:
Brad Marchand - Patrice Bergeron - Jake DeBrusk
Nick Ritchie - David Krejci - Jack Studnicka
Trent Frederic - Charlie Coyle - Craig Smith
Anders Bjork - Sean Kuraly- Chris Wagner
Jeremy Lauzon - Charlie McAvoy
Grzelcyk/Clifton - Brandon Carlo
Jakub Zboril - Kevan Miller
Tuukka Rask should start.
For Pittsburgh, Drew O’Connor was recalled from the taxi squad on emergency basis and will play in his first NHL game.
O’Connor, a former Dartmouth standout, was a member of the 2019 Bruins development camp.