NAPA (AP) — Since Jon Gruden last coached in the NFL a decade ago, the league has undergone a youth movement.

Thanks to a collective bargaining agreement that limits salaries for players in their first four years and a more spread out game that places a greater premium on speed, teams have relied more than ever on young players.

Gruden still is showing the same kind of preference for experience that he did when he first took over the Raiders back in 1998, signing 11 players this offseason who are already in their 30s.

“We’ve added a veteran presence,” Gruden said. “Some people don’t like it, but I like Derrick Johnson, I like Marcus Gilchrist, I like guys that know what the heck is going on.”

That’s the opposite direction most teams have gone since Gruden last coached in Tampa Bay in 2008. The youth movement hit high gear following the 2011 collective bargaining agreement and the average snap weighted age for NFL players fell to 26.46 years last season, according to Football Outsiders, the lowest since the website began tracking that number in 2006.

The average age has been falling gradually each year since 2008, with players about a half-year younger now than they were a decade ago.

But Gruden is bucking that trend, signing players like Johnson, Jordy Nelson, Frostee Rucker and Leon Hall.

“Heck yeah that’s a positive,” tight end Jared Cook said. “It helps the maturity of this team. When you got young guys, especially nowadays, these young guys just don’t get what the NFL is about. Even something as simple as veteran presence and veteran leadership, they don’t understand that. Veteran respect, they don’t necessarily get that. So, having vets in the locker room and having vets around you that know the role, know how things go and that hold other people accountable ... is huge. You can’t buy that anywhere, because vets know how it’s supposed to be done, and they’re going to get it done the right way it’s supposed to be.”

Gruden took a similar tack in his first stint in Oakland, bringing in players like Eric Allen, Jerry Rice, Rich Gannon, Andre Rison, William Thomas, Trace Armstrong and Anthony Newman to help turn the Raiders from a losing team into a playoff participant his final two seasons.

Several of the older players have ties to either defensive coordinator Paul Guenther or special teams coordinator Rich Bisaccia, giving the coaching staff some proven players who are able to help teach the new systems.

“It’s very important,” Guenther said. “I always say this, but it’s a player’s game. So when you have guys that really understand the details of everything. Obviously, we haven’t been through a season with some of the guys who were here last year. Some of the things that come up, whether it be in the locker room or in the meeting room. I may say, ‘Hey, remember when this happened two years ago against Atlanta?’ We recall those things. So it’s very helpful to have guys that are in the infantry line there to help us out.”

The Raiders made an effort to add players like that in every position group on defense with Rucker on the defensive line, Emmanuel Lamur at linebacker, and Reggie Nelson and Leon Hall in the secondary all familiar with Guenther’s defense and able to serve as sounding boards for their teammates.

Rashaan Melvin said he frequently turns to Hall, who spent nine seasons in Cincinnati when Guenther was a defensive assistant or coordinator.

“Any time we’re putting in a new defensive scheme or whatever it might be, he’s been in the system for a long time,” Melvin said. “If it’s a nickel position, he knows it. If it’s the corner position, he knows it. So, whatever questions we might have to ask or to ask coach, he’s like another coach for us in the room.”

But as much as the older players were brought in for their knowledge, it won’t matter at all if they still can’t play at a high level. They need to be much more than unofficial coaches on the field.

The next few weeks will show what these veterans still have left. The 33-year-old Nelson, who has already impressed his coaches and teammates, is trying to prove that his dropoff last season had more to do with Aaron Rodgers’ injury than his advancing age.

“The thing that you hear about that he can’t run anymore, that’s false,” quarterback Derek Carr said. “I can tell you, he’s one of the fastest skill guys that we have still. He can run. You see that by his route running. If he can win on underneath routes that means DB’s are scared about what he can do over the top. He’s still Jordy Nelson, that’s for sure.”

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