Cardinals inside linebackers Kevin Minter (51), Andrae Kirk (49) and Kenny Demens (54).

In 2013, the Cardinals had one of the best defenses in the NFL, and it was spearheaded by Karlos Dansby and Daryl Washington.

The inside linebacker duo was impressive in coverage, a threat to blitz and solid against the run. They were so versatile that coach Bruce Arians never had to think twice about substitution patterns because Dansby and Washington could do it all.

"It slows the game down when you have guys of that caliber," said third-year linebacker Kenny Demens, then a practice squad rookie.

As attention shifts to the upcoming 2015 season, the Cardinals would love for a similar pairing to come to fruition. Free agent

signee Sean Weatherspoon has shown impressive flashes since entering the league as a first-round pick in 2010, and Washington has long been a force when he's been on the field.

However, there's a large gulf between dream and reality, and because of that, inside linebacker has one of the highest variances for success of any position group for the Cardinals.

Weatherspoon has missed 25 games the past two years, including all of 2014 with a ruptured Achilles tendon. Washington was suspended last year for violating the NFL's substance abuse policy, and if and when he gets reinstated, will face punishment for a domestic violence incident in 2013.

Weatherspoon is healthy now, but Washington's absence looms large, as the team searches to fill that hole.

"Obviously he brings another dynamic to this defense," said Kevin Minter, the starting inside linebacker alongside Weatherspoon in OTAs. "I'm not going to take anything away from him because D-Wash was something special. At the same time, I think like we can hold our own ourselves. We hope everything works out, but in the meantime, I feel like we're solid."

The Cardinals have a lot of options to use next to Weatherspoon and hope a player seizes the opportunity. Minter, a former second-round pick heading into his third season, will look to resume his role in run-stopping packages. Kenny Demens and Glenn Carson were backups last year and aim to take another step forward.

Former Bears linebacker Darryl Sharpton was added, while four undrafted free agents, highlighted by BYU's Alani Fua (who is currently out with a foot injury), were recently signed to compete for a spot.

Last year, Larry Foote was signed to a cheap one-year deal, and he proved vital in the middle of the defense, while safety Deone Bucannon was used at linebacker in passing situations. Foote is currently coaching the inside linebackers and Bucannon has moved back to safety for OTAs, and while the possibility exists for both to return to the position – Foote hasn't announced his retirement – the current inside linebackers hope that's unnecessary.

"We've all, at some point in time, had starting roles," Minter said. "We know what it takes to step up and be those guys, and we can be that."

In each of the past two seasons, the Cardinals added an impact inside linebacker – Dansby and Foote – well after the free agent frenzy of March. General Manager Steve Keim was expected to consider one in the draft this year, but he went a different route with his seven selections.

Minter considers it a sign of respect the front office didn't add an early draft pick to the inside linebacker group, and believes the current personnel can slow the chatter of a needed upgrade at the position. Then, if Washington does return later in the season, his presence will be a luxury, not a necessity.

"We're the quarterbacks (of the defense), and if they feel like we can be that quarterback, then what's the point of getting someone else?" Minter said. "I understand bringing in other guys from around the league, but I think they like where we're at right now. I feel like they feel they can win with us, and that's pretty cool."