The Pittsburgh Steelers defense allowed the fewest passing yards of any team in the league last season, largely thanks to an improved contribution out of their secondary.

As the seasons have passed, Steelers cornerbacks have become more adept at man coverage, increasing their effectiveness in defending passes as a result.

While last season wasn't the best for Pittsburgh in terms of interceptions, the cornerbacks still had themselves quite the year. Things have changed somewhat this season (both William Gay and Bryant McFadden are gone), but that won't be much of a setback to what has become an ever-strengthening area of the Steelers' defense.

Let's take a look at the four corners on the Steelers roster who are set to make the biggest impact in 2012.

 

Ike Taylor

131687837_crop_exact Taylor's talent and experience guarantees no one will be fighting to take his job away.
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Ike Taylor is guaranteed to hold onto his starting job this summer. There is a battle going on for the other job, yes, but Taylor's under no threat to be supplanted by the other three corners likely to be on the Steelers' 53-man roster.

Last season, Taylor had 44 total tackles and two interceptions. His athleticism has led the Steelers' charge toward more man coverage. He should again have a strong season, especially considering the league's overall shift to more pass-heavy offensive attacks.

 

Cortez Allen

136007569_crop_exact Cortez Allen will be fighting it out to get time as the Steelers' nickel corner this year.
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At first, it appeared that second-year player Cortez Allen would be the main competition for Keenan Lewis in the battle to take the starting cornerback spot that once belonged to William Gay after he left in free agency for the Arizona Cardinals.

However, it now seems like he'll be vying for the starting nickel job with Curtis Brown, another second-year player.

Allen had just 15 total tackles last year as he saw just 60 defensive snaps while he worked to get more comfortable in Dick LeBeau's defensive system. Primarily, he was a special teams contributor until later in the season.

 

Keenan Lewis

130978852_crop_exact Keenan Lewis is the favorite to win the starting job that belonged to William Gay last season.
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It's not a foregone conclusion just yet that Keenan Lewis will get the starting spot opposite Ike Taylor, but it's seeming more and more likely the job is his to lose. This will be Lewis' fourth season in Pittsburgh and he has the advantage of being more comfortable in LeBeau's system.

Lewis had 37 tackles last season and an interception. This year, he believes he's going to make a major impact and has predicted a Pro Bowl appearance in his immediate future.

Lewis played in 40 percent of all defensive snaps last year, giving him much-needed on-field experience that will only help him lock down the starting job during this offseason.

 

Curtis Brown

124713400_crop_exact Second-year player Curtis Brown could see time in the nickel as he continues to learn the Steelers defense.
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Curtis Brown certainly needs more time to acclimate himself to the Steelers defense, considering he spent his first year as a rookie without OTAs and minicamps during the lockout. However, he's definitely in the mix when it comes to seeing time as the team's nickel corner this year.

Brown had 14 tackles last year. Like Allen, he spent most of his time contributing on special teams. With a full offseason, Brown should be more comfortable taking the field this season, and as such, should see more snaps.