Best Remaining 2015 NFL Free Agents at Every Position

It's been about a month (March 10) since the NFL's free-agent period opened, and while many of the marquee names have long been snatched up, a veritable cavalcade of serviceable players still remains on the market.

In this slideshow, we'll examine the best remaining options at each position—and in doing so, we'll determine why they remain unsigned. We'll discuss their past performances, ages, injury concerns and recent forms.

Here are the best remaining 2015 NFL free agents at every position.

Quarterback

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Michael Vick, New York Jets

Michael Vick still possesses excellent speed, but he didn't exactly dazzle last year in place of an ineffective Geno Smith (1-2 as the starter). Vick only completed 52 percent of his passes and turned the ball over four times, living up to his billing as a 34-year-old backup quarterback. He does have a ton of experience (110 career regular-season starts) and guile, but his best days are behind him.

Tarvaris Jackson, Seattle Seahawks

Tarvaris Jackson has proved to be a decent quarterback over his time in the league, earning a record of 17-17 as a starter. The former second-round pick (2006, Minnesota) has a good arm and excellent mobility and was a favorite of Seahawks head coach Pete Carroll. Jackson isn't good enough to be a full-time starter, but clubs could do worse at the backup spot.

Jason Campbell, Cincinnati Bengals

Jason Campbell has fluctuated from backup to starter over the course of his nine-year career, but he is most certainly a competent option who can step in when needed and not lose games by his lonesome. He owns a 32-47 record as a starter, but that's mostly due to playing on bad teams—as evidenced by his career ratio of 87 touchdowns to 60 interceptions.

Running Back

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Steven Jackson, Atlanta Falcons

Steven Jackson is nearing the end of his career, which has been one of the more underrated ones of the past 15 years. While he did rush for seven touchdowns last season, the 31-year-old is clearly not the player he once was when starring in St. Louis.

Any team that signs Jackson with the expectation that it would be adding a workhorse back is insane, but he can still play a valuable role on a team, moving the chains in short-yardage situations and spelling the starter.

Chris Johnson, New York Jets

After being selected in the first round of the 2008 draft, Chris Johnson exploded onto the scene as one of the league's fastest players—and solidified his status as one of the game's best backs by rushing for 2,006 yards in 2009. But Johnson hasn't been able to keep up that run of form, and he only rushed for 663 yards last season for the Jets. There's no doubting Johnson's speed, but he's not an efficient back at this point in his career (age 29).

Ahmad Bradshaw, Indianapolis Colts

Ahmad Bradshaw helped the Giants claim two Super Bowl championships (2007 and 2011), but injuries have limited him to only 13 games played over the past two seasons. Bradshaw is the epitome of a gamer, and at age 29, it stands to reason that he can still contribute at a high level—provided he can avoid the injury bug.

Wide Receiver

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Michael Crabtree, San Francisco 49ers

Expectations for Michael Crabtree were sky-high following a sterling end to the 2013 season, but he disappointed in 2014, hauling in only 68 passes for 698 yards and four touchdown receptions. The former 10th overall pick of the 2009 draft has dazzled in the past, and it's not impossible that he could recapture that form. The most likely scenario for Crabtree is signing a one-year deal in the hopes that he can rehabilitate his image in 2015—thus earning a larger payday in free agency next year.

Greg Jennings, Minnesota Vikings

Greg Jennings was a free-agent bust for the Vikings, catching only 127 passes in two seasons in the Twin Cities. And at age 31, he's not the player he once was in Green Bay when he was reeling in receptions from Brett Favre and Aaron Rodgers. But he's still a viable option and should be a contributor for whichever team ends up signing him.

Jerrel Jernigan, New York Giants

The Giants had high hopes for Jerrel Jernigan when they selected him in the third round of the 2011 draft, but his potential never quite materialized in the Big Apple. Jernigan caught a grand total of 38 passes in four seasons and only appeared in 34 games. He still has talent—thus his high draft status—but teams shouldn't expect much from the Troy product.

Tight End

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Jermaine Gresham, Cincinnati Bengals

Jermaine Gresham—the 21st overall pick of the 2010 draft—played well last season for Cincinnati in place of the injured Tyler Eifert, blocking with aplomb (he finished 2014 ranked as Pro Football Focus' third-best pass-blocking tight end) and catching 62 passes for 460 yards and five touchdown grabs. While offseason back surgery has quieted down his market, Gresham should be back to his old tricks in 2015.

James Casey, Philadelphia Eagles

After an excellent season in Houston in 2012 (34 receptions including three touchdown grabs), James Casey signed a free-agent deal with the Eagles. But two underwhelming seasons followed, and he was released. He possesses a hybrid skill set, as he's effective both catching the football and serving as a fullback.

Rob Housler, Arizona Cardinals 

After catching 45 and 39 passes in back-to-back seasons (2012 and 2013), Rob Housler fell off a cliff in 2014, only hauling in nine receptions for 129 yards. Ian Rapoport of NFL.com recently reported, via Kevin Patra of NFL.com, that Housler will soon be visiting the Cleveland Browns, who are in dire need of a pass-catching tight end.

Offensive Tackle

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Jake Long, St. Louis Rams

The former No. 1 overall pick in the 2008 draft, Jake Long was released by the Rams after two seasons with the club. While a member of the Dolphins, Long earned two first-team All-Pro nods and four Pro Bowl berths. However, he struggled to stay healthy in St. Louis, suffering knee injuries in both 2013 and 2014. He's only 29, and his past performance means he'll definitely find a new home—perhaps even back in St. Louis at a discounted rate.

Joe Barksdale, St. Louis Rams

While Joe Barksdale isn't proficient in pass protection, he's an absolute road grader in the run game, finishing 2014 as Pro Football Focus' 11th-best run-blocking tackle. He's durable, having started 29 games over the last two seasons for the Rams, and at age 26, he has a lot left in the tank.

Anthony Collins, Tampa Bay Buccaneers

The Tampa Bay Buccaneers signed Anthony Collins to a big-money deal prior to the 2014 season, but things didn't go according to plan. He didn't have a good season, finishing 2014 as Pro Football Focus' 63rd-ranked tackle, and he was released by the club earlier in the offseason. At age 29, he'll likely get another opportunity to play, and it's worth noting that he played good football in Cincinnati prior to signing in Tampa, so the talent is there.

Offensive Guard

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Justin Blalock, Atlanta Falcons

Justin Blalock, 31, played well last season in Atlanta, finishing the year as Pro Football Focus' 25th-best guard. He's a proficient pass-blocker who would fit in well with a team that is looking to air it out.

Dan Connolly, New England Patriots

Dan Connolly—a perennial fan favorite in New England—started 13 games last year for the Super Bowl champion Patriots and once again proved to be a vital cog in the interior of the offensive line. Plus, he was responsible for this play, which is about 5,000 different kinds of epic.

Daryn Colledge, Miami Dolphins

Since being drafted in 2006, Daryn Colledge has started at least 13 games in every season, so he's proved to be durable. He's also versatile, having played both left and right tackle in addition to guard. 

Center

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Chris Myers, Houston Texans

Chris Myers finished 2014 ranked as Pro Football Focus' 16th-best center and is proficient in a zone-blocking scheme. He earned two Pro Bowl berths in seven seasons in Houston and is excellent in the run game, which makes it likely he'll find a home in the near future.

Stefen Wisniewski, Oakland Raiders

Stefen Wisniewski is young (26), has experience (61 starts) and is excellent in the run game. While his pass-blocking isn't superb, his overall skill set is impressive, and he was the 22nd-ranked center in 2014 by Pro Football Focus.

Brian de la Puente, Chicago Bears

Brian de la Puente played in only eight games for the Bears last year but still finished the year ranked as Pro Football Focus' seventh-best center. He's only 29 and is versatile, having also played guard during his career.

Defensive End

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Dwight Freeney, San Diego Chargers

The 35-year-old Dwight Freeney might have 111.5 sacks during his career, but he struggled over the last two seasons in San Diego. His best days are clearly behind him, but the seven-time Pro Bowler can still get the job done as a situational pass-rusher.

Mathias Kiwanuka, New York Giants

Mathias Kiwanuka was a key contributor on two Giants Super Bowl teams (2007 and 2011), but his play fell off in 2014, as he managed only 2.5 sacks in 11 games played. At age 32, there might not be much gas left in the tank, but his versatility—he's played both linebacker and defensive end—should help him earn another job.

Da'Quan Bowers, Tampa Bay Buccaneers

Da'Quan Bowers never quite lived up to the billing of being selected in the second round of the 2011 draft, compiling only seven sacks in four injury-riddled seasons. But the talent is there, and clubs are always in need of pass-rushers, so even with the lack of production, Bowers should get another shot.

Defensive Tackle

Rick Osentoski/Associated Press

Barry Cofield, Washington Redskins

Barry Cofield didn't play well in an injury-shortened 2014 campaign (eight games played with three starts), but the 31-year-old still has gas left in the tank. He has 19.5 career sacks from the defensive tackle position and was excellent in 2013, so he could author a bounce-back campaign in 2015.

C.J. Mosley, Detroit Lions

C.J. Mosley played in 15 games for the Lions last year (starting eight) and compiled 2.5 sacks. He can stop the run and also get after the opposing quarterback, so expect him to find another team soon.

Kevin Williams, Seattle Seahawks

The seemingly ageless Kevin Williams (now 34) can still get it done as a situational run-stuffer, finishing 2014 ranked as Pro Football Focus' 40th-best defensive tackle. With 179 career starts under his belt, he'll bring experience and veteran leadership to whichever team signs him.

Outside Linebacker

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Lance Briggs, Chicago Bears

Lance Briggs—one of the most beloved players in Bears history—finished 2014 ranked as Pro Football Focus' 10th-best outside linebacker. And he did so despite only appearing in eight games, highlighting his excellent play. He's 34 years old, so he doesn't have many years left, but he could still contribute at a relatively high level in 2015.

John Abraham, Arizona Cardinals

John Abraham suffered through an injury-shortened 2014 (he only played in one game), but that shouldn't take away from what's been a remarkable career. Abraham has 133.5 sacks to his name and has displayed the versatility to perform as either a 4-3 defensive end or 3-4 outside linebacker. He'll provide pass-rushing oomph to whichever team signs him.

Jacquian Williams, New York Giants

Jacquian Williams finished 2014 ranked as Pro Football Focus' 30th-best outside linebacker. He's only 26 and can also contribute on special teams, so he should find a team shortly after the draft.

Inside Linebacker

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Brandon Spikes, Buffalo Bills

Brandon Spikes is one of the premier run-stopping linebackers in the league—but that is his primary source of production, as he's a two-down player. He would add a thumping presence to any team that is seeking a boon to its run defense.

Kelvin Sheppard, Miami Dolphins

It doesn't speak well for the remaining options at inside linebacker that Kelvin Sheppard is on this list. The 27-year-old appeared in 14 games last year in Miami and failed to distinguish himself. His most notable career achievement is being traded from Buffalo to Indianapolis for Jerry Hughes, which is one of the great ripoffs of this century.

D.J. Williams, Chicago Bears

D.J. Williams finished 2014 ranked as Pro Football Focus' 40th-best inside linebacker. The former first-round pick (2004, Denver) is now 32 and has only appeared in 25 games over the past three seasons.

Cornerback

Gene J. Puskar/Associated Press

Ike Taylor, Pittsburgh Steelers

Since being selected in the fourth round of the 2003 draft, Ike Taylor has started 140 games and helped the Steelers win two Super Bowl championships. But he only played in five games last season—and at age 34, it's unclear if he'll play in 2015, as Taylor told Gerry Dulac of the Pittsburgh Post-Gazette that he'll consider television opportunities if he retires.

Tarell Brown, Oakland Raiders

The 30-year-old Tarell Brown finished 2014 ranked as Pro Football Focus' 75th-best corner, failing to intercept a pass for the second consecutive season. He did start 14 games last year for Oakland, and his play was better than the statistics would indicate.

Charles Tillman, Chicago Bears

Charles Tillman has been a beloved member of the Bears since being drafted in 2003, and he has been a living, breathing forced turnover, with 36 interceptions and 42 forced fumbles under his belt. Injuries have limited him to only 10 games over the past two seasons, but the 34-year-old should get another shot in 2015.

Safety

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Bernard Pollard, Tennessee Titans

Bernard Pollard has earned a reputation as a bone-rattling hitter and is perhaps best known for knocking Patriots quarterback Tom Brady out for the entire 2008 season in Week 1. He finished 2014 ranked as Pro Football Focus' 36th-best safety. He has 12 career interceptions and 106 starts to his name.

Stevie Brown, New York Giants

Stevie Brown played in eight games last year for the Giants, finishing the year ranked as Pro Football Focus' 47th-best safety. The 2012 season was his magnum opus—he intercepted eight passes and forced two fumbles—and while he's been unable to replicate that sparkling form, he's only 27, so there's still time for Brown to make it happen.

Brandon Meriweather, Washington Redskins

The hard-hitting Brandon Meriweather totaled three sacks and three forced fumbles last year for the Redskins, displaying an all-around game that belied the notion that he's merely a headhunter.

Kicker/Punter

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Jay Feely (K), Chicago Bears

When Jay Feely subbed for an injured Robbie Gould last year in Chicago, it marked the sixth team of his 14-year career (he went 3-of-4 on field-goal attempts). At age 38, he's nearing the end of the line, and 2015 could present his last opportunity to be a full-time kicker.

Mike Nugent (K), Cincinnati Bengals

A former second-round pick (2005 by the Jets—don't worry, we'll wait until you stop laughing), Mike Nugent has kicked for four teams, including spending the last five seasons in Cincinnati. He converted 26 of 33 attempts last year.

Brett Kern (P), Tennessee Titans

The 29-year-old Brett Kern finished 2014 ranked as Pro Football Focus' ninth-best punter, averaging 46.8 yards per attempt.