Defensive lineman Frostee Rucker (98) and rookie Ed Stinson (72) are among those who will help fill the void post-Dockett injury.

Defensive ends Kareem Martin and Ed Stinson were drafted in May with an eye toward the future.

After the season-ending knee injury to Pro Bowl defensive tackle Darnell Dockett on Monday, the focus must be recalibrated to the present.

While Martin and Stinson are still expected to be backups on the defensive line – Frostee Rucker will slide into the starting lineup – both will get increased playing time as the Cardinals work by committee to replace Dockett's production.

"Any time a guy goes down, somebody else has to step up and take the load," defensive end Calais Campbell said.

"We've got young guys who have the ability to be great players in this league.  Usually you have a little time to grow up. Because of this situation now, they've got to grow up a little faster."

One of General Manager Steve Keim's stated goals this offseason was to add depth to the defensive line. Last year, reserves Alameda Ta'amu and Rucker played well when filling in for the starters, but the unit didn't go deeper than that. With Martin, Ta'amu and Stinson backing up Campbell, Rucker and Dan Williams, the Cardinals believe they have enough solid pieces to weather the storm.

"(Dockett) was an integral part of this defense for the past 10, 11 years," Martin said. "Being able to fill that role is going to be tough, but as a D-line I think we have the tools to definitely do it."

Rucker started all 16 games in 2012 with the Browns, finishing with 48 tackles and four sacks. He had 11 tackles and one sack in limited duty last year with the Cardinals, but said he's more than ready to take on a bigger role once again.

"I've been preparing myself like I was a starter," Rucker said. "In this league, you've got to be very professional. You've got to take care of your body, watch film, do all the little things and the big things. That's what I'm all about."

Martin had 11½ sacks last season at North Carolina, and coach Bruce Arians said he was pleased with the job he's done in passing situations, although his run defense needs some work. Stinson is more of a run-stopper who Arians said has "made great progress."

Martin and Stinson will likely keep their same roles, while the biggest change on the line could be playing nose tackles Williams and Ta'amu together. Williams is not the same natural pass-rusher as Dockett, but could move over to end in certain situations to get the team's best package on the field.

"I played it a little bit last year toward the end of the season, trying to spell Calais and Dockett for a few reps," Williams

said. "I'm definitely going to do anything the coaches ask me."

The team added two more options on Wednesday, signing veteran linemen Isaac Sopoaga and Ryan McBean to one-year contracts.

Time will tell if the Cardinals can adequately replace Dockett on the field, and there's also a question as to how the team will respond without his leadership. Dockett and wide receiver Larry Fitzgerald have the longest tenures on the team, and Dockett brings a fiery presence.

"He brings so much emotion and leadership, it's something that's so hard to come by," center Lyle Sendlein said. "A lot of times it's uncomfortable for guys to stand up in front of the team and talk, and very few times when a guy stands up and talks does everyone listen. Dockett is one of those guys."

While Campbell is also a decorated veteran, he is not as naturally outspoken as Dockett. He said he will make a concerted effort to fill that void as the younger players look to him for guidance.

"I was kind of second-in-command, I guess," Campbell said. "I tried to speak up and be a leader already, but now I have to step up and be a vocal leader even more, because he was our vocal and emotional guy before games, breaking down the huddle and getting everybody hyped. Even in practice, when things were going wrong, he was the one that got us together."

Dockett's injury is the latest blow to a defense that looks much different from 2013. Linebacker Karlos Dansby left in free agency and linebacker Daryl Washington was suspended for the season, making Dockett's departure the third key loss.

With Rucker's promotion, there could be six new starters on defense in the season opener if safety Tyrann Mathieu isn't ready by then. Arians downplayed the losses of Dansby and Washington when they occurred, and still believes in the defense without Dockett.  

"Injuries, they happen," Arians said. "It's terrible for him, a great opportunity for somebody else. Frostee will step into that role, the young guys will step up and we'll keep moving on like we always do. One injury is not going to change who we are and what we do."