MOBILE, Ala. — As Jay Gruden and the Redskins conducted their search for a new defensive coordinator, they had a choice to make: Totally reinvent themselves and change to a 4-3 scheme, or continue sporting a 3-4 front. They chose the latter, hiring Joe Barry, who has spent the past four years helping coach the 3-4 defense of the San Diego Chargers.

Gruden said he believes the Redskins’ personnel is best suited for a 3-4 front. He referenced outside linebacker Ryan Kerrigan, inside linebacker Keenan Robinson and nose tackle Chris Baker as key pieces of the defensive front that he wants Barry to develop and build around.

But sticking with the 3-4 doesn’t mean the Redskins will continue to do everything the same way. He wants the unit to become more aggressive in the way it attacks. And Gruden said just because the 3-4 will serve as the base front, there will be plenty of alignments that feature a 4-3 look, as was also the case before, with Washington’s nickel packages.

“I think the personnel that we have — you know, the Ryan Kerrigans of the world. I think it’s a natural fit,” Gruden said. “You know, we’re gonna mess with the way we do the 3-4, you know? There will be some different ideas that we have, as far as it’s not a two-gap 3-4. It might be more of a shoot-the-gap-type of 3-4, a get-up-the-field-and-rush-them 3-4, you know what I mean? There’s going to be some variety involved in that. In this day and age, with as much nickel as you see, there’s a lot of 4-3 elements anyway, but the way we do our base defense, it will be a 3-4 starting point. Once the ball is snapped, what we’re going to do is going to be different.”

The continuation of the 3-4 will come as welcome news to many of Washington’s defensive players.

On the day Jim Haslett and the team parted ways, Kerrigan said that he believed that he was best suited for the outside linebacker position and that in the past four years, he had made a complete transition from college defensive end to linebacker, and hoped to continue to grow rather than having to start all over again.

Washington’s talent evaluators also agree that Kerrigan isn’t the prototypical 4-3 NFL end, although at times, he does rush out of a three-point stance.

Barry and the Redskins do have decisions to make regarding the pieces in place, and the holes on the unit, however.

The first questions involve which assistants to keep. Secondary coach Raheem Morris, linebackers coaches Brian Baker and Kirk Olivadotti and defensive line coach Jacob Burney all remain under contract. Barry coached under Morris at Tampa, and according to people with knowledge of the situation, would like to retain Morris while also changing the way the Redskins do things on the back end.

Barry, himself a linebackers coach, could have different people in mind or different methods in mind for how he wants the linebackers to be coached, although Baker and Olivadotti are well respected by team brass and players. And Burney’s ways of coaching the line could possibly differ from how Barry prefers.

“Way too early,” Gruden said when asked about decisions on the assistants.

“We’ll go through that,” he said. “First thing was get him in place then we’ll talk about the assistants we already have in place and then other options that are available. We’ll start that as soon as we get back to D.C.”

Then there are questions about the rest of the personnel.

Baker opened 2014 as the starting left end, but moved to nose tackle when Barry Cofield got hurt, and he never relinquished the job, despite some inconsistencies. Is he a true nose tackle, or is it best to move him back to end?

Jason Hatcher really is best suited as a 4-3 defensive tackle, and never really settled as the disruptive end the team hoped for. How should he be used?

Brian Orakpo is a free agent, and the team must find a dominant pass rusher to use opposite Kerrigan.

Defensive end Jarvis Jenkins will become a free agent, inside linebacker Perry Riley Jr. struggled with consistency as he played alongside Robinson, and aging linemen Barry Cofield and Stephen Bowen both have high cap numbers, as does Hatcher.

The Redskins see cornerbacks Bashaud Breeland and David Amerson as keepers, although Gruden said that Barry needs to help Amerson get better. There are only two safeties, Phillip Thomas and Akeem Davis, under contract.

What’s ahead:

Mark Bullock takes a look at Joe Barry’s defensive beliefs, and his history.

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