Grzelcyk (leg) didn't practice Monday, Joe Haggerty of Boston Hockey Now reports.

EDGE Analysis

Coach Bruce Cassidy has indicated that Grzelcyk -- who missed Saturday's win over the Flyers -- is considered day-to-day, Eric Russo of the Bruins' official site reports. If Grzelcyk remains sidelined Tuesday against the Penguins, look for Connor Clifton to continue to fill in on the team's second defensive pairing, alongside Brandon Carlo.