Smith, who has battled a groin injury all season, was expected to play his first game of the season Sunday against the Oakland Raiders, but was downgraded Thursday, according to The Florida Times-Union's Ryan O'Halloran. Smith was limited in practice Wednesday.
Wide receiver Laurent Robinson and safety Dwight Lowery also did not participate Thursday.
Robinson, who is suffering from a concussion, also missed Wednesday's practice. Robinson suffered the injury against the Cincinnati Bengals in Week 4. Lowery is expected to be out 2-3 weeks with an ankle injury.
Defensive tackle Tyson Alualu and center Brad Meester both practiced fully Thursday after not practicing Wednesday for non-injury related reasons.
Defensive end George Selvie (knee) practiced fully, while safety Dawan Landry (knee) was limited.
As of 4:30 p.m. ET Thursday, the Raiders have not released their injury report.
Kickoff is scheduled for 4:25 p.m. ET Sunday on CBS.