The Ravens' leading tackler from last season, Smith had predicted that he would return to practice soon, downplaying the severity of the injury.
The Ravens are holding a free, open practice at Navy Marine Corps-Memorial Stadium.
Meanwhile, several other players aren't practicing.
That includes cornerback Marrio Norman due to an undisclosed injury, cornerback Lardarius Webb (back spasms), nose tackle Terrence Cody (hip surgery), wide receiver Michael Campanaro (bruised ribs), offensive guard Will Rackley (concussion) and defensive end Brent Urban (torn anterior cruciate ligament).
Urban will undergo surgery eventually to repair the damage to his right knee when swelling subsides and will be placed on injured reserve.
The Ravens are at the NFL roster limit of 90 players.