Peterson and defensive rookie award

The Arizona Cardinals' Patrick Peterson seems like a logical early candidate to challenge for NFL defensive rookie of the year.

One thing to consider, however: No defensive back has won the award since Charles Woodson in 1998. Nine linebackers and three defensive linemen have won the award since Woodson won it. Since then, NFL teams have drafted 43 defensive linemen and linebackers -- but only 19 defensive backs -- among the top 10 overall choices.

Peterson was the only defensive back selected among the first 18 picks this year. This year tied with 2009 for the lowest number of defensive backs taken in that range over the past 10 drafts. There have been three or four defensive backs taken among the top 18 in seven of the past 10 drafts.

Texas A&M pass-rusher Von Miller (Denver Broncos) and Alabama defensive tackle Marcell Dareus (Buffalo Bills) were the first two defensive players selected this year. Peterson was the third, followed by Missouri's Aldon Smith (San Francisco 49ers), Wisconsin's J.J. Watt (Houston Texans), Auburn's Nick Fairley (Detroit Lions), North Carolina's Robert Quinn (St. Louis Rams), Purdue's Ryan Kerrigan (Washington Redskins) and Illinois Corey Liuget (San Diego Chargers).

All but Peterson are defensive linemen, linebackers or projected outside linebackers. I still think Peterson is well-positioned to contend for the award. He's joining a secondary filled with playmakers. He'll have chances to pick off passes, most likely. And whatever value he adds in the return game will raise his profile.

I also think Fairley should have a strong chance lining up next to Ndamukong Suh. He could rack up sacks. Miller, Dareus, Peterson and Fairley would be my early favorites. The other defensive players drafted early could play situational roles as rookies or play positions that make standing out more difficult. Defensive ends in 3-4 schemes have a harder time making an obvious impact.