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The NFL's free-agent market looks like the grocery store shelves shortly after a hurricane warning is issued.

There isn't much left.

Although some big-name offensive players remain available, the pickings are slim on defense. Almost every proven pass-rusher and cornerback is off the board. This reflects the value of those positions in a league that continues to make the running game a lesser priority compared to throwing the football.

There is no rush for clubs to sign free agents with offseason programs now concluded. But as training camps open in late July and preseason injuries mount, teams will give another chance to players whose stars have faded from previous years.

Here's a look at 10 of them, why they're unemployed and what the future may hold for their NFL careers:

Running back Cedric Benson

Last team: Cincinnati

Why unemployed: Despite finishing with his third consecutive 1,000-yard rushing season in Cincinnati, Benson’s production declined sharply late in the 2011 campaign. The normally sure-handed Benson fumbled five times, losing two of them, in Weeks 15 and 16 and saw his carry totals steadily decline in the final four games. Benson, whose off-field baggage led to a one-game NFL suspension last year, didn’t do himself any favors in Cincinnati when making comments critical of his role in coordinator Jay Gruden’s offensive system. The Bengals moved on by signing running back BenJarvus Green-Ellis away from New England in free agency.

NFL future: Benson could find a new home in Oakland. The Raiders lost a big-bodied running back like Benson when Michael Bush left via free agency to Chicago. The 29-year-old Benson would provide insurance behind starter Darren McFadden, who has yet to complete a 16-game season since being drafted in 2008.

Running back Ryan Grant

Last team: Green Bay

Why unemployed: Grant started 14 games last season and averaged 4.2 yards an attempt, but he didn’t display the same burst after suffering a horrific leg injury in 2010. The Packers are now expecting James Starks and 2011 third-round pick Alex Green to carry the rushing load.

NFL future: If Starks and Green are unimpressive during the preseason, the Packers could consider re-signing the 29-year-old Grant as a stop-gap measure. Such a move wouldn’t be unprecedented. Because of injuries, Packers general manager Ted Thompson re-signed Ahman Green in 2009 after he had spent the previous two seasons with the Houston Texans.

Left tackle Max Starks

Last team: Pittsburgh

Why unemployed: Starks suffered a torn anterior cruciate ligament in last season’s first-round playoff loss to Denver and is still rehabilitating. Although well-liked by team management, Starks may no longer have a spot with the Steelers once he is fully recovered. Mike Adams, the 2012 second-round draft pick, is the new projected starter.

NFL future: If he receives a clean bill of health, Starks will become the top available left tackle. Atlanta should take a long look at Starks, who has 80 starts in eight NFL seasons. The Falcons have the league’s shakiest left-tackle situation with Sam Baker, Will Svitek and rookie Lamar Holmes set to compete for the starting spot in training camp.

Wide receiver Plaxico Burress

Last team: New York Jets

Why unemployed: Burress’ ability to re-launch his NFL career after a two-year prison sentence was commendable. Burress, though, wasn’t the same difference-maker with the Jets last season as he was from 2005-08 with the New York Giants.

NFL future: Burress’ off-field past isn’t as big a concern as the fact he turns 35 in August. Burress isn’t a special-teams contributor, which limits his appeal as a backup. Burress did have eight touchdown catches in 2011 and still can use his 6-foot-5 frame to create scoring opportunities in the red zone, which would make him appealing to a team that needs a starter in a pinch.

Wide receiver Braylon Edwards

Last team: San Francisco

Why unemployed: Injuries and unreliable hands have kept Edwards from reaching the heights expected after his 1,289-yard receiving campaign in 2007. Edwards had only 15 catches in nine games last season, including five starts, before being waived in December after a knee injury. Edwards is still rehabilitating and has yet to take a free-agent visit this offseason.

NFL future: Like with Burress, Edwards’ inability to contribute on special teams limits his appeal. Edwards, though, is an outstanding blocker and had success getting open deep before his failed stint in San Francisco. Cincinnati, which reportedly had some interest in Edwards earlier in the preseason, could be an option if none of the team’s young wideouts are ready to start opposite A.J. Green.

Quarterback Donovan McNabb

Last team: Minnesota

Why unemployed: McNabb’s slide from his glory days in Philadelphia continued in 2011 with the Minnesota Vikings. McNabb tallied only four touchdown passes in the first six games, losing five of them, and struggled to complete downfield passes. McNabb was granted his release in December when it became clear Christian Ponder would start the remainder of the season. The fact that Chicago — a team desperate for quarterbacking help after losing Jay Cutler (thumb) — didn’t sign McNabb speaks volumes about where things now stand in what has been a standout NFL career.

NFL future: The 35-year-old McNabb isn’t ready for life after football just yet. McNabb told NBC Sports Talk last week that there was an “80 to 90 percent” chance he would play this season and there are “about three teams I'm looking at.” Whether those unnamed franchises are looking at McNabb is unknown. McNabb’s best chance of returning to the NFL may come if a team loses its starting quarterback to a long-term injury and wants a veteran under center.

Defensive end Andre Carter

Last team: New England

Why unemployed: Carter was enjoying a Pro Bowl season for New England with 10 sacks when he suffered a season-ending quadriceps injury in December. The Boston Herald recently reported that Carter, 33, is seeking a long-term deal. That may not be in the offing from a franchise that rarely tenders them to older players.

NFL future: If the Patriots haven’t budged in giving wide receiver Wes Welker a multiyear contract extension, it’s difficult to believe they would give one to Carter, especially with New England choosing three players for its front seven (ends Chandler Jones and Jake Bequette and linebacker Dont’a Hightower) in the first three rounds of April’s draft. A one-year deal with Carter like the one he played under last season is a more likely scenario. Carter also must show he is sufficiently recovered from his torn quad.

Tight end Jeremy Shockey

Last team: Carolina

Why unemployed: Shockey’s play remains in decline from his heyday with the New York Giants (2002-07). Shockey caught a career-low 37 passes last season for Carolina, which has shown only nominal interest in re-signing him as a backup to Greg Olsen.

NFL future: Shockey and ex-Minnesota starter Visanthe Shiancoe are considered the top two unsigned tight ends. The 31-year-old Shockey probably has one NFL season left in his battered body, but he is considered a complementary player at this point.

Guard/tackle Vernon Carey

Last team: Miami

Why unemployed: With the Dolphins seeking more nimble linemen under new head coach Joe Philbin, Carey isn’t expected to re-sign with the franchise that made him a 2004 first-round draft pick.

NFL future: Having notched 107 starts in eight seasons, it’s surprising that Carey hasn’t landed with a new squad. Carey, 30, likely will join a team that has a need at right tackle or is seeking a swing backup at tackle and guard.

Safety Jim Leonhard

Last team: New York Jets

Why unemployed: Undersized at 5-8 and 188 pounds, Leonhard has ended the past two seasons on injured reserve with leg injuries. Leonhard’s latest setback was a torn patella tendon suffered in December against Kansas City.

NFL future: While a return to the Jets can’t be completely ruled out, New York addressed the safety positions during the offseason by signing free agents LaRon Landry (Washington) and Yeremiah Bell (Miami). Leonhard is one of the NFL’s most cerebral safeties, but he must convince potential suitors his 29-year-old body can hold up for an entire season and that he didn’t lose any speed from last year’s knee injury.