Mitchell was recalled from AHL Providence on Thursday.
Mitchell was placed on waivers by the Bruins on Friday, Elliotte Friedman of Sportsnet reports.
Mitchell was recalled from AHL Providence on Saturday, Mark Divver of the New England Hockey Journal reports.
Mitchell was loaned to AHL Providence on Sunday.
Mitchell was summoned from AHL Providence on Tuesday.
Mitchell was demoted to AHL Providence on Monday, per CapFriendly.
Mitchell was brought up from AHL Providence on Sunday.
Mitchell was reassigned to AHL Providence on Saturday.
Mitchell was called up by Boston on Friday, per CapFriendly.
Mitchell was on the ice for the Bruins' practice session Friday, Fluto Shinzawa of The Athletic reports.