Johnson re-injured his right hamstring in the fourth quarter of Carolina's 27-22 win Sunday over the New Orleans Saints. Rivera said Monday he doesn't know the full extent of the injury, but hopes Johnson can return after the Week 5 bye.
Middle linebacker Luke Kuechly has made solid progression in the concussion protocol could return to work this week after missing the last two games, according to Rivera.
The fifth-year coach also said wide receiver Jerricho Cotchery will ''probably'' miss his second straight game against the Bucs with a high ankle sprain, but that running back Jonathan Stewart (leg) is expected to play.
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