Mutter signed a one-year, two-way contract extension with the Bruins on Thursday.
Mutter was traded to Boston from Nashville in March, and he recorded a goal, 23 PIM and a minus-2 rating over 12 regular-season appearances with AHL Providence. He'll remain with the organization during the 2026-27 season, but it's unclear whether he'll be in the mix to make his NHL debut at some point next year.