The Raiders are known to be more defense-minded entering the March 14 start of free agency than they were at this stage in 2017.

Oakland Raiders defensive end Khalil Mack (52) and defensive end Denico Autry (96) combing to sack Kansas City Chiefs quarterback Alex Smith (11) during the fourth quarter at Oakland Coliseum. (Kelley L Cox-USA TODAY Sports)

The only veteran defender the Raiders signed last offseason received a one-year contract worth up to $2 million. Of it, $100,000 was fully guaranteed. Linebacker Jelani Jenkins came cheap and left quick, failing to make the roster out of training camp.

That was it.

Not one defensive lineman. Not one defensive back. Not one linebacker of consequence. The Raiders, underwhelmed with the defensive class, invested elsewhere in free agency before — for a second straight year — drafting a defender in the first, second and third rounds with negligible immediate returns.

A new offseason soon will begin in earnest.

It shall feature a new approach.

The Raiders are known to be more defense-minded entering the March 14 start of free agency than they were at this stage in 2017. To some degree, they have little choice, given their breadth of preexisting roster needs compounded with key impending free agents. Scheme change under new defensive coordinator Paul Guenther also is a factor.

Guenther seeks a specific mold for defensive linemen on which his system is predicated. League sources familiar with the team’s approach indicated the Raiders are fully expected to be players in free agency for linemen deemed a fit for it.

Specific free-agent targets won’t be known until closer to free agency’s start. Defensive lineman Denico Autry’s contract expires on March 14. Linebacker NaVorro Bowman and cornerback TJ Carrie are the other main, in-house free agents on defense.

“He wants to get guys getting off the ball and creating havoc and making plays and being physical up front,” general manager Reggie McKenzie said last week at the NFL combine in Indianapolis. “That’s always been said, but he’s got a plan on how he wants to use guys. So we know exactly what he wants.”

The Raiders plan to build their cornerback group around 2017 first-round pick Gareon Conley.

Ideally, they will find a starter opposite him in free agency. Sean Smith, due $8.25 million in salary, is expected to be released. David Amerson already has been. Carrie is coming off a career year. Even if Carrie is re-signed, work figures not to be done.

Contracts for assistant coaches often carry a two-year structure.

When the Raiders hired Guenther and offensive coordinator Greg Olson, there were reports their deals were of the four-year variety. Sources recently have corrected that, stating that both are under three-year deals. Nonetheless, under coach Jon Gruden and his 10-year pact, a level of stability accompanies this staff which enables McKenzie to better pair players with the coaches tasked to develop them.

“To me, you always want to get the best players,” McKenzie said. “Great coaches like we have, they’re going to put them in the right spot. I’m not a fan of just getting a guy who can only do this one thing. But that’s where you plug holes. When you’re talking about the draft and grooming your own players, you want to get the right-fit guys, guys who can do multiple things and have some type of versatility.

“When we meet with the coaches, that’s what we get out of it. Exactly what do you guys want? And then, we can just go to work.”

The Raiders largely possess the same roster needs on defense today than in March 2017. Those include interior rusher, linebacker, cornerback and safety.

This year, free agency should represent a start.

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Contact reporter Michael Gehlken at mgehlken@reviewjournal.com. Follow @GehlkenNFL on Twitter.