CHARLOTTE, N.C. (AP) Cam Newton returned to practice Wednesday eight days after a horrific-looking automobile accident left him with two fractures in his lower back.
Whether or not he starts Sunday against the Cleveland Browns remains unclear.
Panthers coach Ron Rivera said the team put Newton through a ''rigorous'' rehab schedule and will now wait to see how much soreness the fourth-year quarterback has on Thursday. Rivera wouldn't say definitively if he'll start Newton or Derek Anderson in a game with playoff implications for the Panthers (5-8-1).
The Panthers are a half-game behind the New Orleans Saints in the NFC South with two games remaining.
''Come Friday I want to have a good feel for him,'' Rivera said. ''I don't want to let it drag or linger. We want our quarterbacks to know who's getting the reps if they're going to be the starter.''
Newton, wearing a long sleeve black shirt under his red practice jersey and a helmet, was limited in practice according to the team's injury report and split reps with the first team with Anderson. Rivera said Newton looked good throwing, even heaving a few balls more than 60 yards downfield.
Rivera said Newton could see an increased workload this week if he feels good.
Rivera repeatedly said Thursday is ''a big day'' for Newton.
''They put him through some very rigorous stuff today with the intention to stress (the back) and see how he feels,'' Rivera said.
Newton did not address the media, but is scheduled to talk on Thursday.
While sitting as his locker Wednesday, Newton was asked how he felt and pretended to zip his lip as he smiled at reporters. He said nothing of his injury.
''I thought he looked pretty good and move around normally,'' tight end Greg Olsen said of Newton.
Olsen said he doesn't anticipate Carolina's game plan changing much if Newton doesn't play, and said the uncertainty over who is starting shouldn't affect the team's preparation.
''Both guys have been in this offense long enough and it doesn't matter,'' Olsen said. ''So if we haven't gotten it by now, we'll never get it.''
Newton missed last week's game against the Tampa Bay Buccaneers after flipping his truck in a two-vehicle wreck on Dec. 9. Newton suffered two transverse process fractures and was hospitalized overnight after the crash.
The fourth-year quarterback is 3-8-1 this season as Carolina's starter. Anderson is 2-0 with both wins coming against the Buccaneers (2-11).
Browns coach Mike Pettine is preparing as if Newton will start at quarterback. He said the more athletic Newton poses more problems from a preparation standpoint than Anderson.
''The things they do with Cam with the quarterback runs and the options and the things you won't necessarily see when Derek is in there,'' Pettine said. ''They just pose more problems schematically. So it's obviously in our best interest to prepare for him.''
Anderson said he expects Newton will try to start if he feels healthy enough to play.
''It's out of my control,'' Anderson said. ''I have to be tuned in and have a very good understanding of what we're going to do and understanding their defense and what they're trying to do to us. If I am called upon to play, I will play.''
Anderson left Cleveland in March of 2010 under tense circumstances.
The Browns released him two years after he appeared in his first and only Pro Bowl.
After his hasty departure, Anderson sent an email to The News-Herald in Cleveland that read: ''The fans are ruthless and don't deserve a winner. I will never forget getting cheered when I was injured. I know at times I wasn't great. I hope and pray I'm playing when my team comes to town and (we) roll them.''
If Anderson starts on Sunday it will be his first against his former team.
Anderson described his experience in Cleveland on Wednesday as ''up and down'' and ''wonderful at times.''
''I said some things I regret saying before I left,'' Anderson said. ''But it's over with and I've moved on. I'm happy. I wasn't in a great place when I left. I'm in a lot better place now.''
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