When the Arizona Cardinals lost veteran defensive lineman Darnell Dockett for the season with a torn ACL, they lost the heart and soul of their team.

His loss will affect the team.

But it won't necessarily be on-field production they lose.

Dockett was once one of the most feared defensive players in the game. He was the guy offensive coordinators schemed around.

That hasn't been the case the past three seasons.

He saw a dip in production under Ray Horton. That was in part because of how he was used and partly because he was unhappy with that role. His production increased last season with Todd Bowles. He had 4.5 sacks and 46 tackles.

However, the sack numbers are deceiving. Three of those sacks came against the New Orleans Saints when he was lined up against Tim Lelito, an undrafted rookie making his first NFL start. He was playing in pace of the injured Jahri Evans, a fantastic guard.

I point this out not to criticize Dockett, but to note that what he provided in on-field production can be replaced.

Veteran Frostee Rucker will now step into the starting lineup. He has been a starter in the league. He was a starter for the two seasons prior to coming to Arizona last year. Playing in Cleveland in 2012, Rucker had four sacks and 48 tackles. Over the last three seasons, Rucker has one-half less sack than Dockett, but has done so in less playing time.

Rucker has played very well during camp and the preseason so far.

The Cardinals drafted defensive lineman Ed Stinson in the fifth round this year. Now he will be able to play significant snaps. He has also looked great.

The truth was that the Cardinals were going to have more defensive linemen than they could viably play before Dockett's injury.

Last year, they had a five-man rotation on the line -- Dockett, Rucker, Calais Campbell, Dan Williams and Alameda Ta'amu.

This year, they would have had seven on the roster once Ta'amu returns from his torn ACL. They would have had Dockett, Williams, Campbell, Stinson, Ta'amu, Rucker and third round pick Kareem Martin.

Between Rucker and Stinson, Arizona can get 4.5 sacks and 46 tackles. That's not the issue.

What is the issue is his presence, his heart and his leadership.

Arizona has suffered big leadership losses. Karlos Dansby left in free agency. Yeremiah Bell retired. Dockett is now done for the year. John Abraham missed half of training camp after a DUI arrest.

But the team also added veterans Antonio Cromartie and Larry Foote. They recently signed Desmond Bishop. Calais Campbell and Patrick Peterson should also become vocal leaders.

Yet the loss of Dockett is deflating. He has been the vocal leader for the team ever since Bruce Arians arrived. While he can still be in the locker room with the team, he will not be able to be at practice. They will lose his voice on the field and off. His presence will be there with the team, but it won't be the same. He will be in the training room while the rest of the team is in the weight room or on the practice field.

That is the loss that you can't quantify.

They will be able to make up the production Dockett had on the field, but will the defense be able to have the same mentality and toughness without its emotional leader? That is the bigger question mark right now.