2012 free agency opens on the afternoon of March 13. Here's a look at some of the top players on defense...

DEFENSIVE LINEMEN
*Calais Campbell
Mario Williams
Robert Mathis
*Sione Pouha
Jason Jones
Cliff Avril
John Abraham
Paul Soliai
Mark Anderson
Kendall Langford

LINEBACKERS
Curtis Lofton
Dan Connor
D'Qwell Jackson
David Hawthorne
Anthony Spencer
Stephen Tulloch
London Fletcher
Joe Mays
Ahmad Brooks
Jarret Johnson
Philip Wheeler
Quentin Groves
Jameel McClain
Manny Lawson
Jo-Lonn Dunbar
Leroy Hill
E.J. Henderson
Barrett Ruud

CORNERBACKS
Brent Grimes
*Cortland Finnegan
Brandon Carr
Carlos Rogers
Terrell Thomas
Rashean Mathis
Aaron Ross
Eric Wright
Richard Marshall
Tracy Porter
Marcus Trufant

SAFETIES
Tyvon Branch
LaRon Landry
Dashon Goldson
Michael Griffin
Dwight Lowery
Thomas DeCoud
Jim Leonhard
Brandon Meriweather
Reggie Smith
Sean Jones
Mike Adams
Chris Harris
Reggie Nelson

* = likely will be franchise tagged.

COMPLETE LIST (NFLTradeRumors.com)

NFL 2012 nfl free agents, defense