SPARTANBURG, S.C. – Carolina Panthers coach Ron Rivera doesn’t yell much, so when he does it tends to get everyone’s attention.

Such was the case Tuesday, when the mild-mannered Rivera ripped into players at midfield after what he called a “chippy” practice that included plenty of pushing and shoving, a few late hits and one “melee” involving more than a dozen players.

With his fists waving up and down, an angry Rivera warned players about the dangers of losing their cool in practice.

“We can’t have chippiness or late shots toward a teammate,” Rivera said afterward. “The concern obviously is it escalates and it festers and it lingers and the next time we go out on the football field somebody is taking a shot …

“We can’t afford to have anybody that we truly need get caught up in this.”

The Seahawks open their regular season Sept. 8 at Carolina.

There were several confrontations during the Panthers’ morning practice, the biggest being a heated altercation between the offense and defense involving more than a dozen players by the time quarterback Cam Newton and others pulled players from the scrum.

“You have to look at it like a double-edged sword,” Newton said. “On one hand, you have to like the fire in the guys. But at the same time, you have to be respectful of guys’ careers. When a fight breaks out, anything can happen.

“For something that can be just for kicks and giggles, somebody can get a sprained ankle or hurt. So that was coach Rivera doing his fatherly due diligence, trying to protect his players and express to us to play smarter.”

Tight end Greg Olsen took exception to a perceived late hit near the sideline from safety D.J. Campbell and retaliated by chucking the ball at Campbell.

Rivera warned players if they can’t abide by his rules they will sit out.

What concerned Rivera the most is that some receivers were hit downfield while they were in vulnerable positions.

Notes

• Green Bay receiver Jordy Nelson will miss the rest of training camp after undergoing a procedure on one of his knees.

Nelson joins other Packers on the sideline, including left tackle Bryan Bulaga, who is expected to miss the season because of a torn knee ligament — though reportedly Bulaga hasn’t given up on the idea of playing.

• Wide receiver Riley Cooper returned to the Philadelphia Eagles after a four-day excused absence to undergo sensitivity training because he was caught on video yelling a racial slur before a Kenny Chesney concert.

Cooper, who is white, was fined by the team but not suspended. He said he talked to each teammate, face to face, and apologized.

“I told them, ‘I don’t want you to forgive me. That puts the burden on you. I want it all on me.’ I apologized,” Cooper said.

“They could tell it was from the heart. They know I’m not that kind of person.”

• Eagles receiver Arrelious Benn has a torn ligament in his left knee and will miss the season.

• San Diego receiver Danario Alexander tore a ligament in his right knee in practice and will be lost for the season.

Alexander caught 37 passes for 658 yards and seven touchdowns in the final nine games last season.

• Defensive end Everrette Thompson, a former Washington Huskies player who has an arm injury, was placed on the waived-injured list by the Arizona Cardinals.

• Beleaguered quarterback Mark Sanchez, who is competing for the starting job with rookie Geno Smith, will start for the New York Jets in the team’s exhibition opener Friday in Detroit.