Firkser reverted to the Lions' practice squad Monday, per the NFL's official transaction log.
Firkser was elevated to the active roster ahead of Sunday's 34-27 overtime win against the Giants, failing to record any stats while playing three snaps on offense and seven snaps with the special-teams unit. The tight end finished as a distant second option at his position with Brock Wright logging 60 snaps on offense, but he did finish ahead of Ross Dwelley (2). With Sam LaPorta (IR, back) likely sidelined for the rest of the regular season, Firkser should have another opportunity to be elevated in the near future.