Arizona Cardinals offseason: The outlook of the defensive line

After completing our review and outlook of all the position groups on offense, we now move to the defensive side of the ball. We begin the the defensive line.

The roster:

Calais Campbell, signed through 2016
Darnell Dockett, signed through 2015
Tommy Kelly, will be unrestricted free agent
Kareem Martin, signed through 2017
Josh Mauro, signed through 2016
Frostee Rucker, signed through 2015
Ed Stinson, signed through 2017
Alameda Ta'amu, will be restricted free agent
Dan Williams, will be unrestricted free agent

Looking at 2014:

The line played very well for most of the year. They lost Dockett in the preseason and his loss and the team's subsequent reaction set the tone for the season. They found treasure in another team's trash when they signed Tommy Kelly late in training camp to take Dockett's spot and went on from there.

Campbell was a wrecking ball, getting seven sacks and earning his first career trip to the Pro Bowl.

Frostee Rucker played a crucial role all season. He played limited snaps and was hampered early in the season with a calf injury, but filled in nicely in Dockett's role. He had five sacks and 27 tackles. Dockett had 4.5 sacks in 2013.

Dan Williams played very well, although his numbers won't always show it because of his role at nose tackle. However, he did see more playing time and played more than just nose tackle. He saw some time in some nickel/dime packages, something he had never done before. He even picked up a key sack in one of the team's victories.

Kelly had a sack and 41 tackles, playing all over the line.

Arizona added young blood to the rotation. They drafted two linemen. Kareem Martin, a bit of a project, disappointed. Touted as a young pass rusher, he only had one sack. He struggled for playing time and when he got it, he wasn't impactful for the most part. But he has development to do still.

The team's fifth round pick, Ed Stinson, ended up playing a very key role. He only collected nine tackles, but his ability to occupy space was important for the run defense. When he ended up on injured reserve, there is no coincidence that the run defense fell apart.

Josh Mauro was a nice find late in the season.

Ta'amu was the biggest disappointment of the season. Coming back from a torn ACL, he recovered quickly. His effectiveness never did, though. He was absolutely dynamic and disruptive against the run in 2013. He only played 24 snaps in 2014. It was one of the untold stories of 2014 because of the early success of the team and the defense -- he just fell out of favor of the coaches.

The big questions:

Darnell Dockett enters the final year of his contract coming off a torn ACL and representing nearly $10 million against the cap. His contract will have to be addressed. As the soul of the Cardinals, you don't want to see him go, but his production was replaced. He was not really missed on the field, except after his replacements got hurt, too. He doesn't seem willing to take a pay cut and head coach Bruce Arians plans on his returning. We will see.

The other big question is about Big Dan Williams. He will be a free agent. Can they afford to bring him back? Can they afford not to?

Looking ahead to 2015:

Free agency could hit this group hard. Williams will be a free agent. Ta'amu is not under contract. Kelly is a free agent as well. Dockett might be a salary cap casualty.

There is a report that projects Williams could command $6 million per year in a new free agent contract. Williams plays roughly 30 percent of the defensive snaps. Can the Cardinals afford to pay a guy that much who plays that little? At the same time, what will happen to the run defense if he goes? He might be the most important piece to the puzzle.

What makes Williams' likely departure tough is that Ta'amu was no good in 2014. After his 2013 season, despite the injury, with Ta'amu under control through 2015 (as a restricted free agent), Arizona was prepared for Williams to leave in free agency. Now, I don't think anyone thinks the team can count on Ta'amu, for whatever reason.

Arizona will try to bring back Kelly, though he is 34 years old. I would expect a deal much like Rucker's last year -- two years for about a million dollars per year. But that also depends on whether Dockett is brought back.

Stinson will play a key role again and Martin will have to make step forward in his development.

Free agency:

There will be a few big names hitting the market -- players like B.J. Raji, Ndamukong Suh and others. Philosophically, the Cardinals have not gone after top defensive linemen. Those are players best drafted. Look for some lesser known younger player to be a target or a veteran who has been a starter in the past (like Tommy Kelly or Frostee Rucker before they joined Arizona).

NFL Draft:

While I don't have specific names, you have to think that they will take a hard look at nose tackles. I would be surprised if the team didn't draft at least one defensive lineman.