Tolbert was placed on the injured reserve/designated to return list Tuesday. Under that designation, Tolbert can practice after six weeks, but isn't eligible to play until Nov. 30 at Minnesota.
The bruising fullback was injured on a tackle involving ex-Panthers safety Mike Mitchell in Carolina's 37-19 loss to Pittsburgh on Sunday night.
Tolbert had seven rushing touchdowns last season.
Carolina signed linebacker D.J. Smith to fill Tolbert's roster spot.
The 6-foot, 240-pound Smith attended training camp with the Panthers and was on their practice squad before being released on Sept. 3. Smith has played in 23 games with nine starts. Smith has 80 career tackles, two sacks and one interception.
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