2012 NFL Free Agents: 5 Best Under-the-Radar Defensive Signings

The 2012 free-agent class contains some noteworthy bargains plenty of teams should consider snapping up. These are scheme-versatile players who have endured injuries and adapted to positional switches to produce a solid level of play.

Players like San Diego Chargers inside linebacker Stephen Cooper and New England Patriots pass-rusher Mark Anderson represent great value in this year's defensive market. Mario Williams, Cortland Finnegan and Paul Soliai will command the biggest fees.

However, this unheralded group would be smart acquisitions, capable of contributing in any system. The following five players are the best under-the-radar defensive signings on the 2012 free-agent market.

1. Mark Anderson, DE, New England Patriots

Speedy edge-rusher Mark Anderson became an effective weapon in the New England Patriots' hybrid defensive schemes. He has shown the versatility to be a pressure threat in both 4-3 and 3-4 fronts.

The 28-year-old has the quickness, range and athleticism to attack from a four-point stance or act as a stand-up rusher. Anderson racked up 10 sacks last season and can generate pass rush from either side of the line of scrimmage.

The 6'4", 255-pounder is not particularly stout against the run. However, the ability to collapse the edge and get to the quarterback from any front makes Anderson a valuable pickup.

With the Patriots seemingly set for an inevitable defensive revamp following last season's 31st overall ranking, Anderson may not be back for a second season in New England.

2. Pat Sims, DT, Cincinnati Bengals

Injuries have blighted the short career of Cincinnati Bengals defensive tackle Pat Sims. However, if he can stay healthy, the 26-year-old would be an excellent signing for any team looking to add some power and aggression up front.

At 6'2" and 330 pounds, Sims has the size and strength to anchor the interior and be a force against the run. His underrated quickness and solid hands technique makes Sims a decent interior-rush threat.

He is capable of applying constant pressure to the pocket and freeing up pursuit lanes for linebackers and quicker, more active linemen. Sims has played his whole pro career in a 4-3, but he has the physical attributes and temperament to be an effective nose tackle for a 3-4 team in need.

The Bengals already rely on complementary tackle duo Geno Atkins and Domata Peko. With Nick Hayden also in reserve, Sims could end up being the odd man out in Cincinnati.

3. Stephen Cooper, LB, San Diego Chargers

Veteran Stephen Cooper is an intelligent linebacker with the smarts and instincts to direct play in both a 3-4 and 4-3 defense. The nine-year pro missed 11 games last season but if he's healthy can still be highly productive.

Cooper is a cerebral player with an excellent ability to read offensive formations and diagnose plays. He directed the San Diego Chargers' No. 1-ranked defense during the 2010 season. He previously operated in a 4-3 with the Tennessee Titans under Jeff Fisher and Jim Schwartz.

Cooper has a good understanding of zone concepts and is an asset in coverage, where he uses his anticipation to make big plays. At 32 he may be experiencing some wear and tear after last season's injury problems, but Cooper still has enough left to be a key addition to a number of defensive schemes.

With the Chargers expected to bring back Takeo Spikes, now could be the time for Cooper to find a new home. 

4. Dwight Lowery, S, Jacksonville Jaguars

Dwight Lowery enjoyed a successful conversion to safety with the Jacksonville Jaguars in 2011. He has the speed, range and versatility that should make him appealing to any team seeking safety help.

Lowery's form was one of the bright spots on an otherwise dismal Jaguars team. He recorded 36 tackles, notched a sack, defensed eight passes and snared two interceptions.

This year's free-agency safety class is dominated by Tennessee Titans standout Michael Griffin and hard-hitters like Oakland Raiders star Tyvon Branch and LaRon Landry of the Washington Redskins. However, teams should not be quick to overlook Landry. He is a savvy and flexible player who is able to man either safety position.

5. Terrell Thomas, CB, New York Giants

He may have lost the entire 2011 season due to a serious ACL injury, but Terrell Thomas is still an intriguing prospect for any team looking for a starting corner. If he can prove his fitness, Thomas would be a cheaper alternative to the likes of Brandon Carr, Cortland Finnegan and Brent Grimes.

Thomas collected 10 interceptions in the two seasons before his injury. He is an aggressive, tall and rangy ball hawk who would provide a major boost for a pass defense that struggles to make big plays.

A naturally physical corner, Thomas is also extremely capable in run support and could act as an excellent force player in Cover-2 schemes. The New York Giants have promising youngster Prince Amukamara and incumbents Corey Webster and Aaron Ross all vying for playing time.

Equipped with a positive health report, Thomas would be a smart, under-the-radar defensive signing who could make a major impact in 2012.