CHARLOTTE, N.C. (AP) Cam Newton hasn't quite recovered from his fractured ribs.
The Panthers fourth-year quarterback was held out of practice Wednesday due to soreness in his ribs. Coach Ron Rivera still thinks Newton will start the season opener Sunday at Tampa Bay.
''I'm optimistic and I expect him to be there,'' Rivera said. ''We will see how it all unfolds. We have to look at this day by day.''
Rivera said he had expected Newton to practice Wednesday. But the two-time Pro Bowler complained or soreness in the morning and after practicing on Monday and working out on the side with the trainers Tuesday.
Newton did not speak with reporters as he normally does on Wednesdays because he was undergoing treatment on his fractured ribs.
Derek Anderson took the first-team reps at quarterback.
Rivera maintains the team's game plan will not change, though it's hard to imagine the Panthers calling any designed ''read option'' running plays if Newton does start. Newton ran for 2,032 yards and 28 touchdowns in his first three seasons in Carolina.
Rivera said it's too early to know if Newton will practice Thursday.
''The nice thing is we have installations in the morning and he will have a good chance to do that, as well as see all of the tapes,'' Rivera said.
Rivera said Newton seems to have settled on an oversized flak jacket that he would wear on Sunday. He had been experimenting with a variety of protective jackets.
''We're going to approach this day by day, but again I'm an optimist,'' Rivera said. ''I'm been wrong before, but we'll see.''
According to ESPN, Newton has been hit 467 times over the past three seasons - more than twice as much as any other quarterback in the league during that span.
''It's his style of play, how he plays,'' Rivera said. ''You would like to see him develop another style of taper his style, but again that is what makes him who he is. If you take too much away from him it changes his game. But I do think it something he has to learn as he matures more and more as a quarterback - how to slide, how to get rid of the ball and how not to take those hits.''
The 31-year-old Anderson has started 43 games during his nine seasons in the league, but none since joining the Panthers three years ago.
His last start came in 2010 with the Arizona Cardinals.
Anderson's best season was in 2007 when he threw for 3,787 yards and 29 touchdowns, earning him a Pro Bowl selection. For his career Anderson has thrown for 9,206 yards with 53 touchdowns and 55 interceptions and has a career quarterback rating of 69.1.
The Panthers kept Joe Webb on the roster as a third quarterback in the event Newton struggled to get back on the field due to injuries. In addition to his ribs, Newton is also coming off ankle surgery in March.
Anderson said he knows the pain Newton is feeling in his midsection. Anderson said tore the cartilage in his ribs in 2009 while playing for Cleveland but still played in a game against the Chicago Bears.
''I probably shouldn't have played,'' Anderson said.
Anderson said his preparation for this week is no different whether he's a backup or a starter.
''Whatever reps I get during the week is great and I try to take advantage of those,'' Anderson said.
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