Patrick Peterson having shutdown corner season thus far

One thing that has come almost unnoticed by many this season with the good start of the Arizona Cardinals is the play of cornerback Patrick Peterson. After signing a huge contract extension before last season and with uneven play for much of last year, he was (justly) criticized for his play.

It was later revealed he was battling diabetes, in addition to head and ankle injuries he suffered early in the year.

Entering this offseason, the talk was about how good he looks and how he is going to get back to the player he was.

Through four games, he has been, and it has been quiet.

In fact, according to Pro Football Focus stats, he has yet to allow 100 yards receiving on the entire year. According to their numbers, he has been targeted only 12 times this season, allowing only four catches for 85 yards. When targeting him, quarterbacks only has a passer rating of 52.4.

He is allowing a catch only once per nearly 32 coverage assignments.

His primary assignment the past two weeks -- Torrey Smith and Kenny Britt -- have been shut out. Not a single catch.

To be fair, he has not faced elite receivers yet. Brandin Cooks was the toughest guy according to most and Peterson really was only "beat" once.

Coming up these next two weeks Peterson has two very big tests. He will face Calvin Johnson and Antonio Brown on the road.

Is he up for the test? The way he has looked says he is. That doesn't mean he will shut them out, but his focus through four weeks has been laser sharp.

Perhaps that is best thing to see. His struggles have typically come from lack of focus. If he continues to focus the way he has, we might be seeing the beginning of what we all have hoped -- a true shutdown cornerback.