Cardinals cornerback Patrick Peterson can't corral an interception last week in Philadelphia.

Every week, when Patrick Peterson prepares for a game, he includes in his studies some notes on which to focus that Sunday.

Before the game in Philadelphia last week, Peterson scribbled "Be a little more vocal" among his self-reminders.

"I thought I did, a little bit," Peterson said with a smile.

It was a small nod to his emotional explosion on the sideline, captured by TV cameras and shown for all to see. Peterson said that incident was "totally separate" from an attempt to talk a little more to his teammates. But in both cases, it underscored Peterson's reality. His contributions as a top-level cornerback are obvious, but the role

also limits how much he can actually help.

With the Cardinals' defense unable to create many turnovers and teams rarely throwing Peterson's way, the Pro Bowler has to find different ways to make an impact.

"I wish I could do more to help contribute to this team, but all I can do is my job the best I can," Peterson said. "I've been doing that the last couple years and the last five weeks. At times it is frustrating. I want to be involved more. I want to get my hands on the ball more. I want to be in the mix more. But it's hard for me when a team avoids me."

Peterson does not have an interception yet this season. He had one slim chance at one against the Eagles, a ball all but thrown out of bounds that Peterson couldn't haul in along the sideline. According to Pro Football Focus, Peterson was only thrown at three times in Philadelphia. He allowed two catches for 26 yards (albeit one of them a crucial third-down conversion on the Eagles' first touchdown drive.)

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If Peterson can continue to play the way he has, defensive coordinator James Bettcher said, that does plenty to impact both the defense on the field and his teammates off it.

"Leadership starts with action," Bettcher said. "That's working hard like he works, in the meeting room, watching the amount of tape he watches, understanding what routes he'll see, understanding every split a receiver is going to give him in every situation.

"To be able to be a leader, you have to handle your own business first. He's a pro at handling his own business."

According to PFF, Peterson has allowed only seven catches this season in five games (with 16 targets), for 82 yards. He's seventh in the league in both cover snaps per target (11.9) and yards allowed per cover snap (0.43), and third in coverage snaps per reception (27.3).

Last week, the Eagles scored on four touchdown passes, but none to No. 1 receiver Alshon Jeffery. Two went to tight ends, two went to wide receivers. The Cardinals are 21st in the league in passing yards allowed even with Peterson's work.

Peterson did have an interception last season against Tampa Bay, which visits Arizona Sunday.

"I'm sure (Patrick) wants more balls to be thrown his way," Bettcher said.

Peterson also wants the Cardinals to play better on defense. His sideline eruption, out of character for him, came from a "number of things collectively."

"I care about winning very, very much," Peterson said.

Normally, Peterson is about every detail, every technique, every chance to prove on tape to a future opponent that he doesn't have any holes in his game that can be exploited. If he can add being more vocal in his toolkit, perhaps that'll add even more value to his presence.

"I have to make sure I'm playing up to par when the play comes my way," Peterson said. "I wanted to make (being vocal) a point of emphasis for myself. Pass that passion on to my teammates."