Tyrann Mathieu began the 2016 season healthy enough to contribute to the Arizona Cardinals after tearing his ACL in December, so head coach Bruce Arians trotted Mathieu out as the team's free safety against the New England Patriots.
Mathieu has always been listed as a free safety for Arizona, but in actuality, his responsibilities in the past were much more diverse than that of the average NFL defensive back.
On two thirds of his snaps last season, Mathieu served as Arizona's nickel cornerback, tasked with shutting down slot receivers in the passing game and acting as an additional perimeter defender against the run. This season, though, Mathieu has yet to return to his role in the slot, and the Arizona defense hasn't been as effective as a result.
The Cardinals didn't need Mathieu as a slot defender against an outmatched Buccaneers squad on Sunday, but Arizona paid the price for his limitations against New England, where all Mathieu could do is watch from a high safety role as Julian Edelman and Danny Amendola torched the Cardinals to the tune of a 10-for-16 conversion rate on third down.
"I didn't feel like I played as well in the Patriots game, but I felt like in the Tampa Bay game obviously, I did my job pretty well," Mathieu said after Wednesday's practice. "I stayed as deep as the deepest and I just tried to make the plays that came to me."
When Mathieu first returned in training camp, we suggested the Cardinals may not use him in a nickel corner role as much this season because the adjustment to playing at full speed would take time. Even though Mathieu is on the field and perceivably "healthy," he's still unable to play up to his maximum capabilities, which he acknowledged Wednesday.
"I think once I get back comfortable, mentally obviously, and physically, just get through the little tendinitis, a little tightness and being sore after the game, I think once I get through that part, I'll know I'm ready," Mathieu said.
Mathieu is considered one of the league's best safeties, and during training camp, he signed the richest guaranteed contract ever for an NFL safety. However, his status as a safety only exists because that's how the Cardinals define him on the team's roster, and if he only played in a single-high role, there's no chance Mathieu would have commanded the type of contract he did from Arizona.
Mathieu has earned his designation as one of the league's elite defensive players because he's a master of one of the most challenging positions in football. Arizona saw first hand how New England exploited free agent signee Tyvon Branch, and Branch is probably in the upper echelon of players capable of manning the nickel corner role.
For Arizona's defense to reach its full potential, it needs Mathieu playing a variety of roles, and it can't have him limited to serving as an over-the-top, last line of defense type of player. Once Mathieu feels capable of adding on defensive responsibilities, he'll need to tell a coach who's waiting on a self-assessment.
"Quickness, speed, him (Mathieu) coming to me and saying he wants to," Arians said of what he needs to see out of Mathieu before Mathieu can return to the slot.
Mathieu said repeatedly after tearing an ACL for the second time in three years that he wouldn't return to the field until he felt 100 percent. In reality, the Cardinals and Mathieu both knew he could contribute effectively in a limited role, and there's no sense in keeping a dynamic playmaker off the field.
While Mathieu isn't quite ready to play nickel corner, the Cardinals know he possesses elite anticipation skills and is an above average player as a high safety. While Mathieu understands the importance of his contributions, the fact he's unable to have more of an impact in a more challenging role eats at him every day.
"Every day it seems to just eat at me, but I've got a lot of good guys around me, they keep me encouraged, they keep me in a positive spirit, so I'm really thankful for that," Mathieu said.