Hyder was injured during the Lions second defensive series on the game at it was apparent nearly immediately that something was seriously wrong.
That’s according to a report from NFL.com which says Hyder suffered a torn Achilles.
The Lions did beat Indianapolis 24-10, although that does nothing to mollify the growing concerns about their mounting injuries at a position that was already among their thinnest.
Hyder, a breakout star who led the Lions last season with eight sacks, was pressuring Indy quarterback Scott Tolzien in the first quarter when he slipped and hit the ground, immediately clutching his lower left leg.
He had been in the mix to start at strong side linebacker and also provided much-needed depth at defensive tackle.
Since joining the Lions, he’s appeared in all 32 games, serving an important function on multiple special teams units.
The Lions are weighing potential replacements at defensive end, but no signing is imminent and might find better a viable pass rusher at roster cut-down day next month.
Meanwhile, free-agent acquisition Cornelius Washington missed Sunday’s game with an ankle injury and Brandon Copeland left with a shoulder injury.