''We told our guys if you get thrown off the field, I'm going to treat you like you got thrown out of a game,'' Rivera said Thursday.
So players wouldn't return to practice.
Dolphins coach Joe Philbin agreed with the approach, and it has worked.
Skirmishes at camps are not new, and to some extent even condoned. But Rivera and Philbin are among a group of coaches around the league who have spoken out to curb the fighting that has garnered training camps headlines in an effort to set the tone for workouts.
And when coaches speak out, their voices are being heard.
Arizona Cardinals coach Bruce Arians said he has no patience for fighting in training camp, issuing a zero tolerance policy. If players fight, they run.
''It's not tolerated here,'' Arians said. ''Coaches that believe in it, they need to get new jobs.''
The Dolphins and Panthers completed two days of fight-free work on Thursday, aside from one very minor scuffle between Panthers offensive lineman Michael Oher and Dolphins defensive end Olivier Vernon on Wednesday.
''We talked to our players about making sure we took advantage of the opportunity,'' Rivera said. ''We didn't come here to be disruptive and fight, we came here to get better as a football team.''
Philbin said he and Rivera took measures before practices to make sure players were getting the message, calling them together in a group near midfield. And once practice started, the Rivera and Philbin split up and went to different fields, each with authority to discipline the opposing team's players.
''I told our team we're not coming here to have a bar room brawl - and If we want to do that, we can stay down in Florida,'' Philbin said. ''We came down here to compete and to get tougher and to get a little more physical against a really good football team.''
Pagano didn't want a repeat of the sideline-clearing brawl that happened earlier this summer between the Washington Redskins and Houston Texans, or even the fights that marred a joint practice between the Dallas Cowboys and St. Louis Rams earlier this week.
''If guys fight, if you do it in the game, they're going to throw you out - and you're hurting the team. So you can't do it,'' Pagano said. ''... Treat them like we treat ourselves. It's not about the chirping and the jaw jacking and taking cheap shots. It's about getting better.''
Baltimore Ravens coach John Harbaugh emphasized to his team before their practices with the Philadelphia Eagles that when you practice together, you have to function as one team - and he felt like the two teams did a good job of that in their first joint workout with coach Chip Kelly's squad.
Saints coach Sean Payton emphasized fighting is not necessary.
''For as much as we are harping about avoiding it, the (NFL) network puts it on 11 times,'' Payton said. '' ... We are both trying to do the same thing at this period of training camp and that is unfortunate when you see it happen with other teams. Clearly when you put a team on television like Hard Knocks and then practice with someone else, we've seen that formula two years in a row so that is nothing new.''
Although several NFL coaches have praised what they've gotten out of joint practices, some coaches avoid it for competitive reasons.
''Had a lot of opportunities to do it,'' Chiefs coach Andy Reid said, ''but probably from a selfish standpoint, in today's world, with technology, there's not a lot of secrets. You have your coaching points, teaching points - you try to teach on the field - and I really don't want anyone hearing that.''
AP Sports Writers David Skretta in St. Josepha, Missouri, Robert Baum in Glendale, Arizona, Brett Martel in White Sulphur Springs, West Virginia, and Mike Marot in Indianapolis contributed to this report.
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