The number shines down on him just like the Napa sun.

“Fifteen sacks,” Bruce Irvin said.

That’s the number that Khalil Mack, Irvin’s new teammate and opposite-end pass rusher, had for the Raiders last season.

“I hope they put three or four people on him and just let me run free,” Irvin said, smiling.

Irvin is reunited with defensive coordinator Ken Norton Jr. after the Seahawks didn’t pick up the fifth-year veteran’s contract option. “I couldn’t have been put in a better situation,” Irvin said.

He sat down for a one-on-one interview after a recent training-camp practice. Among other things, he touched on leadership, being feared, Raiders tradition, Mack, his biggest surprise since joining the team and fights at training camp:

There has been a transfusion of new blood here with you, Sean Smith and Reggie Nelson on defense. What do you bring to the mix?

Irvin: Leadership. And not just talking about it, but leading by example. You have to get guys believing in one thing, and that’s playing for each other. That, and try and get better every day.

When you guys take the field in the season opener against (New Orleans quarterback) Drew Brees, what do you want to be going through his mind when he looks across the field?

Irvin: Fear. We want to be feared. Not just on defense but as a team. We want to be physical and punish people. That’s the biggest thing. We want people to look at the Raiders, and say, “That’s a tough, nasty physical team. ... They’re going to run the ball and they’re going to play great defense.”

Teams can take on the personalities of their coaches. Did you just describe Jack Del Rio and Ken a little bit?

Irvin: Definitely. They’re a couple of bullies, and we’re taking on that bully mentality. But that’s just the Raiders, period. You look at the old teams here, and they would do a little extra after the play. It is what it is. That’s the appearance you want to have, like you will do anything to win.

Did the young core of Mack, Derek Carr and Amari Cooper clinch it for you when you decided to sign here?

Irvin: It’s a young team on the rise. And they added a lot of key pieces in the offseason. I looked at that, too. And playing in a familiar defense with one of the best players in the league in Khalil Mack.

What makes Mack special?

Irvin: Regardless of the success he’s had his first two years in the league, he’s always willing to learn, always willing to see it from my perspective or somebody else’s. He is a very humble person who is going to continue to get better each and every year.

You mentioned the known things coming in. Anything surprise you about your teammates in the offseason workouts and camp?

Irvin: (Middle linebacker) Ben Heeney. I really like Ben. High-motor guy who’s not very big but plays bigger than he is. One thing about Ben is he’s going to leave it out there for you every play. I have a genuine appreciation for that.

A lot has been written about you and Ken. But you’re also reunited with (linebacker) Malcolm Smith, who was the MVP of the Super Bowl you won in Seattle. Have you seen any changes in Malcolm?

Irvin: It’s a new Malcolm, because he is getting an opportunity. He didn’t get a lot of opportunities in Seattle. He’s been given a chance to be a leader and big-time playmaker for us, and he is doing a great job at that.

Do you have a chip on your shoulder about how it ended in Seattle?

Irvin: That’s water under the bridge. I could never thank (coach) Pete (Carroll) and (general manager) John (Schneider) enough for putting me in a great situation and helping me grow as a player and as a man. But it’s time to move on. I feel like I didn’t reach my full potential in Seattle, and I am going to take full advantage of that opportunity here.

You tweeted out that you didn’t want teammates to read the clippings and believe the hype. But ... you peek a little, right?

Irvin: Yeah. … It is always good to be talked about. You get tired of hearing about the other 31 teams. It’s good to get loved on sometimes. But it doesn’t mean anything. So remember that.

What’s the secret to not losing it at training camp? Meetings all day, practices, having a roommate. … How do you ease the grind?

Irvin: You have to go out of your way to make it fun, otherwise you’ll be miserable. It’s draining. So you have to crack a lot of jokes at each other’s expense, shoot hoops …

Who’s the guy to beat in hoops?

Irvin: The defensive backs have a lot of shooters. We have shooting contests, 30 seconds for each guy to make as many as he can, each position group. The last three days, the defensive line has won. Me and Khalil, and Shilique Calhoun and Darius Latham can both shoot.

There have also been some boxing contests between some of your defensive teammates and guard Kelechi Osemele. Is that just part of the camp grind?

Irvin: That’s just who he is. He’s a physical, tough-nosed guy. We just have to get him to understand that we’re all on the same team. You can’t try and hurt your own guy. But he is on a new team. They may have practiced differently in Baltimore. ... He’s a good guy. Going to be a great player for us. Can’t wait to see him out there in the opener. Just another Raiders bully.

Vic Tafur is a San Francisco Chronicle staff writer. Email: vtafur@sfchronicle.com Twitter: @VicTafur