ALAMEDA, Calif. -- As the Oakland Raiders begin the second week of OTA practices Tuesday, just exactly how palpable is the change in attitude for a team that has not had a winning season since 2002?

It is something the Raiders’ longest-tenured position player has never experienced before.

“This is year nine for me (so) I’ve been around a lot of coaches, a lot of players, and this is real belief, you know?” four-time Pro Bowl fullback Marcel Reece said. “Everybody really believes. Everybody knows this is different. Everything is different, even from last year.

One of the longest-tenured members of the Raiders, Marcel Reece is thrilled about the positive energy around the team. Charles LeClaire/USA TODAY Sports

“Everybody saw a lot of growth last year but right now, the state of this team is unbelievable, something that I, personally, have never been around and only dreamed of. So it’s fun being around the young guys, who are keeping me young. And it’s just fun. Football’s fun again.”

Indeed, the Raiders improved from three victories in 2014 to a 7-9 record in Jack Del Rio’s first season as head coach last year.

And after “winning” free agency this spring -- Oakland became a destination for highly sought-after free agents such as offensive lineman Kelechi Osemele, linebacker Bruce Irvin, cornerback Sean Smith and free safety Reggie Nelson -- the Raiders are a popular pick to make some serious noise in the AFC West.

Especially with the free-agent haul joining the young nucleus of All-Pro defensive end/outside linebacker Khalil Mack, quarterback Derek Carr and receiver Amari Cooper.

But being “paper champions” means little at the moment, according to Del Rio.

“I think that’s a nice catchphrase for somebody to write about, but that’s not real,” Del Rio said. “For us, we’re about the work that we’re putting in. It’s real work. There is real sweat being put in. There is real effort and energy being put forth. A real commitment. That’s where our focus is, not on words.”

Reece, meanwhile, still has three games to go on a four-game suspension levied by the NFL after, he said, his ingestion of a natural plant root extract called Umcka resulted in the supplement converting into the banned substance metylhexanamine.

Reece is able to participate in offseason workouts because the offseason part of his suspension was lifted by the league, and Reece remains hopeful he could have the remainder of penalty thrown out too.

The suspension has not affected the veteran’s standing as a team leader in the locker room, Reece said. Only placekicker Sebastian Janikowski, who was the Raiders’ first-round draft pick in 2000, and long-snapper Jon Condo, who was a practice squad signee in 2006, have been in Oakland longer than Reece, who signed with Oakland as a street free agent in 2008.

“Me being transparent and vulnerable with my teammates, as I’ve always been, I think they just know me and know my character and know how I operate,” Reece said. “And they know that I’ve never done anything wrong; I’ve never cheated in any way, shape or form and for me, I’m just trying to fight it the right way, but making sure I keep the team No. 1.

“I’m kind of at peace with the situation as it is now, but at the same time want to get some sort of vindication and, as the young kids say, respek on my name.”