The Pro Bowl player participated in his first full practice Friday night at Fan Fest since undergoing surgery in March.
Newton looked sharp throwing passes but struggled with his footwork and timing on handoffs. He didn't appear to run with a limp until after practice when he jogged over to sign autographs for some of the 36,315 fans in attendance at the team's downtown stadium. The event signaled the official start of training camp for the NFC South champions.
''I can't stress enough that I'm not 100 percent yet,'' Newton said.
At one point Carolina's trainer Ryan Vermillion came over to check on the fourth-year quarterback during practice, but Newton said it was just precautionary.
''It's just going to take treatment and time,'' Newton said, adding that his rehab is right on schedule.
Coach Ron Rivera said the Panthers will take it slow with Newton, making sure to avoid any potential setbacks.
He said Newton will continue to undergo treatment on a daily basis, but was thrilled to see the team's leader back on the field.
Rivera said he hopes to have Newton available for all four preseason games.
''It was good to see Cam out there,'' Rivera said. ''He's a little rusty in terms of his quarterback to running back exchange. But he's working himself back in and he has to work those techniques. But it was nice to see him make some nice throws.''
Rivera said Newton's footwork still needs to improve.
''A big thing is developing that footwork and getting that flexibility back in that ankle,'' Rivera said. ''As he practices and goes through day by day we have to be smart with it. I think he will work back into shape pretty soon.''
Newton had surgery in March after experiencing soreness in his left ankle following Carolina's 23-10 NFC divisional playoff loss at home to the San Francisco 49ers. Newton gave the ankle about two months to improve after the season, but when it was clear it wasn't getting better the decision was made to have surgery.
Newton is coming off a Pro Bowl season in which he threw for 3,379 yards and a career-high 24 touchdowns while leading the Panthers to a 12-4 record and the NFC title.
Newton, in typical fashion, played up to the large crowd that came out to see the two-hour practice on a rare cool Charlotte summer night.
In between drills Newton got the crowd roaring when he started ''the wave'' in the lower bowl of the stadium. A few minutes later, Newton slowed down the speed of the wave with his arms before getting the crowd to shift the direction of the wave.
Newton later drew cheers when he completed a 40-yard pass to rookie wide receiver Kelvin Benjamin, the team's first-round draft pick, near the left sideline.
''This is great,'' Newton said of the turnout, the largest in Fan Fest history. ''We are expecting this turnout every time. They hold us accountable and we have to put a great product out there.''
Defensive end Greg Hardy, who was convicted on July 16 on two domestic violence charges, was also back on the field and was playing up to the crowd, waving his arms up and down in his usual fashion.
Panthers general manager Dave Gettleman said the team is following the NFL's lead and allowing the legal process to play out before handing out any punishment to Hardy. Hardy has appealed the conviction and will have a jury trial.
No date has been set, but more than likely it will not happen until next year.
The Panthers will move training camp practice on Saturday to Wofford College in Spartanburg, South Carolina, on Saturday.
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