Coach Ken Whisenhunt said Thursday that Mount was injured during practice Wednesday in a non-contract drill.
Mount was the Titans' sixth-round draft choice this spring out of Louisville. Mount picked off a Jameis Winston pass in Tennessee's 42-14 win at Tampa Bay to open the season.
Whisenhunt says coaches could see Mount improving unfortunately but now know the linebacker can contribute to the team. The injury will force the Titans to make the first change to their roster since the opening week. Whisenhunt says a move likely will come Saturday.
The Titans (1-3) host Miami (1-3) on Sunday.
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