UPDATE: Cam Newton has been listed as inactive. The Carolina Panthers have announced Derek Anderson will start against the Tampa Bay Buccaneers.

Jay Glazer reported the team was leaning toward starting Anderson on Sunday morning and that the team fears Newton could be out 3-4 weeks.

Newton had been held out of the last preseason game after suffering a fractured rib against the New England Patriots in Week 3 of the preseason.

It was uncertain if Newton would be able to play, and apparently he is not healthy enough yet. Throughout his three-year career, Newton had never missed a game in the regular or postseason until Sunday. In 2013, Newton threw for a career-high 24 touchdowns against 13 interceptions while throwing for 3,379 yards. Newton also added 585 rushing yards and six scores.

If Newton is out, Derek Anderson will make the start. Anderson has been a backup with the Panthers since coming over from the Arizona Cardinals in the 2011 season. Anderson is a veteran but did not throw a pass last season, so he could be rusty.