On Friday, the Detroit Lions will bring their physicality to this summer’s first session of padded training camp practices. It will also mark the first practice open to Lions season ticket holders.

The team’s last two practices have been marked by a high degree of intensity and scuffling. In fact, multiple fights broke out at the team’s Allen Park practice facility Thursday, including scuffles between defensive tackle Brodric Martin and offensive lineman Giovanni Manu and linebacker Anthony Pittman and running back Jabari Small. Brian Branch and Amon-Ra St. Brown were also seen jawing back and forth at one another.

Additionally, Thursday was the second consecutive practice in which Lions head man Dan Campbell had to put a pause to the on-field play because of the excessive physicality.

While Detroit plays a violent brand of football on defense, it’s also important to make sure it’s under control. Lions defensive coordinator Kelvin Sheppard is well aware of that, and believes he and the rest of the defensive coaching staff are on the same page when it comes to their expectations for the unit.

“I told the players the other day in the defensive unit meeting, this isn’t my stuff I’m saying. This is our stuff,” Sheppard said. “I’m not ever going to stand up here and say I’m some genius guru and I invented football. I have allowed my staff to have ownership in their respective positions. I allow input from everyone, from top to bottom. If there’s a ‘why’ behind it, it’s going in. These guys know that, so I think that allows them to work harder. The trust is there, there’s no looking over your shoulder. I don’t have to go into position rooms and wonder what’s being said. I know it’s one voice.”

Check out Detroit Lions on SI all day for updates throughout Friday’s practice: