TEMPE, Ariz. -- When the Cardinals released their depth chart for Sunday's game against Houston earlier this week, there was one noticeable change.
Defensive coordinator Todd Bowles said the move was made because Mathieu gives the Cardinals more options in their schemes and coverages.
"He gives us a little bit more versatility as far as playing man coverage with the tight ends we face and the receivers we face," Bowles said. "Kinda (like) having three quasi corners out there, if you must, and he's still a good tackler as a safety and he has great ball skills and great eye-hand coordination."
Mathieu, who was named the NFC Defensive Rookie of the Month for October, has 45 tackles, two interceptions and a sack this season. He's started six of Arizona's eight games this season and has been on the field for 85 percent of its plays, according to Pro Football Focus. But he'll be more of an every-down defensive back from now on.
In the past, Mathieu has said he could be an every-down defensive back in the NFL, but he understood he needed to prove himself first. After he was drafted, Cardinals coach Bruce Arians wanted to work Mathieu as a free safety in the slot, essentially the third corner that Bowles mentioned. In April, Arians said Mathieu provided the "flexibility where we wouldn't have to substitute."
The decision to make Mathieu a starter validates that.
"I always thought I was a lockdown cornerback in college," Mathieu said. "Just to be out there every day covering wide receivers, it just gives me that opportunity to do what I do best and that's make plays on the ball."
Johnson started four of the six games he played in this season. He missed weeks four and five after losing the tip of his left middle finger against the New Orleans Saints in Week 3. He'll be part of the Cardinals' nickel packages and special teams.
"Nothing against Rashad," Bowles said. "Rashad is a damn good safety.
"He'll play a ton, too, and both of them work off each other. But Tyrann has a little bit better man skills with the people we were going up against at that time. That's why we decided to make the move."
Now that he's a starter, Mathieu understands the responsibility that comes with it. And the opportunity. His goal since draft day was to claim his stake in the NFL through hardware. He said being a starter will give him a chance to win the postseason awards he has his eyes on.
But starting also carries an added responsibility.
"Definitely not the little kid on the team," Mathieu said. "Got to step into more of a leader role and be more vocal. Just keep doing what I've been doing."