MacDermid entered concussion protocol after fighting Milan Lucic in Saturday's game versus the Flames, Peter Baugh of The Athletic reports.
MacDermid doesn't end up on the losing end of many fights, but he got pummeled by the Flames' bruising winger late in the second period. It's unclear if MacDermid will be cleared prior to Monday's game versus the Golden Knights, though the Avalanche could be welcoming back fellow defenseman Cale Makar from a concussion of his own for that contest.