GREEN BAY, Wis. — Maybe they should have posted a sign at Ray Nitschke Field on Sunday that said “For mature audiences only.”

The way shoves, taunts and curse words were being thrown around during the Green Bay Packers’ third training camp practice of the season, a warning probably was in order.

It was the first day of full pads, so it’s no surprise the practice erupted into a grade 3 testosterone storm, especially when you consider it proceeded two days of pitter-pattering around in shorts, jerseys and helmets. The theme of the day was don’t rough up my teammate or I’ll rough up you.

Of course, they’re all teammates, but when offense and defense go against one another certain primal instincts take over.

“It’s pretty common,” guard Josh Sitton said. “I haven’t hit anybody in awhile. Defense is fired up and they’re trying to finish and stupid plays happen. People get tackled. Offensive linemen, our job is to protect our guys. That’s why we’re running down there.”

Sitton cursed a blue streak as he walked back to the huddle after one skirmish, threatening to take on cornerbacks coach Joe Whitt and his entire unit, who had been riding him about the linemen taking liberties on defensive players.

Typical of the way these things go, Sitton wasn’t sure what he said and was surprised to find out that anybody had heard him.

“All that stays on the field,” he said. “That’s just how it is. It’s one of the only professions in the world you can beat the (expletive) out of each other and a couple minutes later it’s like, ‘Ah, all right.'”

There may have been an element of provocation this time around.

The Packers defense has made “579” its cause, snatching the total number of yards the San Francisco 49ers gained in a 45-31 divisional playoff victory off the score sheet and projecting it as a symbol of what must never happen again.

There has been much written about how the 49ers manhandled the Packers defense that day. Whether it’s in response to the 579 or the criticism, the defense came out Sunday with the intention of charging the atmosphere.

“That’s always the goal for the defense to be more aggressive,” linebacker Dezman Moses said. “There’s been a lot of talk about us being soft and this, that and whatever.

“We don’t believe that. That’s never been a question by anyone in this locker room. We’re just trying to up the physicality a little bit. Just make it a way that our defense works and plays.”

Coming out and being fired up in practice doesn’t guarantee a more physical football team. It’s about drafting certain types of players and creating a certain atmosphere. It’s almost impossible to do the second without doing the first.

Whether the Packers are built that way and are trying to reach their inner anger or are just expressing false bravado is something everyone will find out come the season opener against the 49ers. Right now, the idea is to take what they have and begin the process of building a different environment.

“I think it’s just something that happened,” defensive end Mike Daniels said of the scrums. “The competition has increased everywhere. It’s making guys play with that extra little oomph.

“I just try to find reasons to get mad. It’s just the way I play. Not everybody plays that way. That’s always helped me. I look for reasons to try to bring it out. You see it. But it’s not everybody’s game.”

It is defensive end Johnny Jolly’s game, and he was in the middle of the biggest altercation. He didn’t like something second-year guard Andrew Datko did and the two pushed and shoved as teammates quickly came over and joined in.

Jolly was notorious for starting stuff during his first stint with the Packers, and now that he’s back from a drug suspension he doesn’t seem to have lost any of his on-field vigor. It may be something the Packers need from him or someone else if they’re truly going to be a tough defense.

Daniels was asked if he thought the defense would be nasty this year.

“Did you watch practice?” he said. “The nasty is here and I love it. Everybody is getting involved. The best part is, we all understand each other. What happens on the field, stays on the field. It’s kind of like Vegas. When we get back on the field we’re all friends.”

The friendship part is something coach Mike McCarthy would like to preserve. Most important, he’d like to make sure everyone is around the locker room to be a friend and not in the training room palling around with the trainers.

He wants everyone to practice aggressively and hit with their shoulder pads. But he doesn’t want tackling. His biggest complaint is that too many players were knocking each other down to the ground and creating an unsafe environment.

“It was great to get that competitive environment established,” McCarthy said. “I thought they definitely practiced with an edge. We had too much extracurricular activities going on. That falls under your category of player safety.

“We have to practice better together, something that you don’t do every night. This is a normal progression you go through every year in training camp. But I thought our guys came out on the high side of playing with an edge and that’s exactly what we want.”

Did the defense make its point? Receiver James Jones had an answer for that.

“Yeah, they were bringing some nastiness today,” he said. “We’ll get them (Tuesday).”