The Raiders approached free agency intent on building from the inside out, and so far, coach Jack Del Rio likes what he sees.



Included were the acquisitions of defensive tackle Dan Williams, middle linebacker Curtis Lofton and safety Nate Allen on defense, and center Rodney Hudson on offense.

“We strengthened ourselves up the middle in our defense, and offensively, getting Hudson helped us a great deal,” Del Rio told reporters during his press session Tuesday morning at the NFL owner’s meetings in Phoenix, Ariz. “We had a good, solid off-season. It wasn’t sexy. We didn’t get the name receiver everybody is clamoring for. But it was an effective, methodical approach to filling some needs and addressing some issues.”

Del Rio said he and general manager Reggie McKenzie share the same philosophy in that football is won with big people and executing fundamentals such as blocking and tackling.

“As much as we want to talk about the beauty of a ball being thrown and caught on the outside, you’ve got to be able to be strong in the trenches,” Del Rio said. “That remains a central part of what we do in this league.”

The Raiders were believed to be one of several teams who discussed contract parameters with Green Bay wide receiver Randall Cobb during the negotiating window, but Cobb re-signed with the Packers before free agency began.

Philadelphia’s Jeremy Maclin signed with Kansas City, and the Raiders made no move when veterans such as Kansas City’s Dwayne Bowe (who signed with Cleveland) and Minnesota’s Greg Jennings (still on the market) were released.

As it stands, the Raiders receiving corps include returnees James Jones, Rod Streater, Andre Holmes, Kenbrell Thompkins and Brice Butler. None constitute the kind of game-breaking threat the offense desperately needs.

Quarterback Derek Carr averaged only 5.46 yards per passing attempt as a rookie starter, ranking near the bottom of the NFL. Del Rio said that as Denver defensive coordinator, the Broncos weren’t particularly concerned about Raiders receivers getting behind them.

“I think he’s really a good deep ball thrower,” Del Rio said. “They didn’t have a lot of guys that would necessarily scare you in terms of getting deep.”

Most mock drafts have the Raiders going for a wide receiver at No. 4 in the first round on April 30, with West Virginia’s Kevin White and Alabama’s Amari Cooper viable options.

“We don’t feel it’s doom and gloom at the receiver spot,” McKenzie told Sirius XM NFL Radio. “We do know we want to upgrade at the receiver spot and some other spots also. We’re taking a positive outlook because there are some good receivers out there coming into this draft. At some point I’m sure we’ll get better at that position.”

Other observations from Del Rio included:

— The signing of running back Trent Richardson, a former No.3 pick in the draft who was traded by Cleveland and released by Indianapolis.

“What I saw was a young man that was hungry to leave that portion of his career behind him,” Del Rio said. “He’s got to compete for everything he gets. He knows that. I laid that out for him at the start.”

— Speculation on the club moving to Los Angeles next season.

“I just refuse to waste time speculating and wondering what might be and all those things,” Del Rio said. “Obviously I’m not blind to it. I’m aware it’s out there. We’re going to make the most of where we are right now and we’re in Oakland.”

— Poor-fitting helmets _ Del Rio’s pet peeve when it comes to the NFL safety issue.

Del Rio said he believes he had only one concussion at USC and none in the NFL. He said he wore his helmet so tight he needed to use Vaseline to get it over his ears. He promised Raiders players would have proper fitting helmets.

“I played four years of high school, four years of college, practice and played 11 years in the NFL. Not one time did my helmet ever come off. Ever.”