The Bills added Incognito after one year out of football following the Dolphins bullying scandal, and he repaid Buffalo with a Pro Bowl-caliber season. Buffalo has made bringing him back a priority, and the market for Incognito could still be limited by his reputation.
Boldin is still going strong, leading the 49ers with 69 catches this past season at age 35. At his advanced age, it seems unlikely that Boldin will want to stick around for the team's rebuilding under new head coach Chip Kelly.
Jeremy Langford's breakout season makes it unlikely that the Bears will bring back Forte. He's slowed in recently seasons, averaging only 3.9 yards per carry in 2014 and 4.1 yards per carry in 2015. Still, he had 898 yards rushing and 44 receptions this past season.
Weddle all but guaranteed that he'd go elsewhere with his falling out in San Diego last season, and there should be a market for his services despite his age (31). He had 78 tackles in 13 games this past season, after accumulating 100-plus tackles in each of the previous two seasons.
Jenkins has held out for free agency, and the Rams could let him walk with a deep secondary. He's coming off a very good year in St. Louis, with three picks and 64 tackles.
Irvin hasn't quite lived up to the hype as a pass rusher after being selected 15th in the 2012 draft, but he's still been an important piece during Seattle's playoff runs. He had 5.5 sacks in 2015, after getting 6.5 sacks and two interceptions in 2014.
Miami's front seven is among the best in football, but it'd take a hit of Vernon departs. He had 61 tackles and 7.5 sacks this past season.
Injuries have hindered Smith over the last two seasons, as he's missed a combined nine games. Still, Cincinnati's offensive line has been one of the league's best, and the Bengals are likely to make an effort to re-sign Smith.
Hali is starting to show the wear and tear on his body after 10 NFL seasons and 156 games, but he said following the season that he intends to play in 2016. He had 6.5 sacks and 48 tackles in 2015 and has 86 sacks for his career.
Trevathan rebounded from an injury-plagued 2014 season to have 109 tackles in 15 games in 2015. It could be difficult for the Broncos to spend big on both Von Miller and Trevathan.
The Jets will try to retain Ivory after a career year, passing the 1,000-yard rushing mark for the first time and adding seven scores on the ground. He's shed his injury-prone label and become a bell cow back.
Johnson returned from a torn Achilles to have a Pro Bowl-caliber year with the Chiefs, with 116 tackles, four sacks and two interceptions. He's now had more than 100 tackles in five of the last six seasons.
Washington surprised many by anointing Cousins the starting quarterback in training camp ahead of Robert Griffin III. Cousins made head coach Jay Gruden look like a genius, completing 69.8 percent of his passes for 4,166 yards and 29 touchdowns.
New Dolphins head coach Adam Gase is likely to want Miller back with the team after gaining more than 1,200 yards from scrimmage this past season. In fact, Miami could use Miller more often with the perception that he's been underused in recent seasons, even with a career 4.6 yards per carry.
Fitzpatrick's status as a nomad could finally come to a halt, as the Jets are likely to give him a big payday. The Harvard alumnus has started for four different teams over the last four seasons but looked great in the Jets' offense while throwing to wideouts Brandon Marshall and Eric Decker, reaching 3,905 yards and 31 touchdowns.
The Seahawks want to improve their offensive line in 2016, and it's unclear if that will include Okung. While he's been a strong player when healthy, he had injury issues again in 2015. He will get paid well regardless of where he goes.
Pierre-Paul is a major wild card in free agency after missing half of 2015 due to a fireworks accident that damaged his hand. He had only one sack while playing with a club on his hand but should be able to play without the club in the future, and he was one of the NFL's best pass rushers before the accident.
Glenn has developed into an elite tackle during his four seasons in Buffalo and will likely be a priority for the Bills to re-sign. He's also been durable, playing all 16 games in each of the last three seasons.
Jeffery isn't entering free agency in the best place, playing only nine games in 2015 due to injuries. He still managed 54 catches for 807 yards and four scores in those nine games, and had more than 1,100 yards in each of the two previous seasons.
Coming off two seasons ruined by knee surgeries, Bradford's first year with the Eagles could have been better. He threw 14 picks in 14 games but still managed 3,725 yards and 19 touchdowns in Chip Kelly's offense. Even with Kelly departing, new head coach Doug Pederson has said that he'd like Bradford back.
Tampa Bay has Charles Sims as a fallback plan if the team is unable to bring back Martin, but new head coach Dirk Koetter has already said that he'd like Martin back. He had a career year after two injury-plagued seasons, returning to form to gain 1,400 rushing yards and adding 33 catches for 271 yards. He also had seven scores on the Bucs' up-and-coming offense.
The Jets' incredible defensive line depth could be reason for the team to let him walk, if not his hefty price tag. Wilkerson had a career year in 2015 with 12 sacks and 64 tackles.
The NFL's Comeback Player of the Year will likely become the league's highest paid safety, returning as an elite player less than one year after being diagnosed with cancer. The Chiefs got big production from him, including 61 tackles and two interceptions.
Norman has become a household name just in time for free agency. The Panthers cornerback had a breakout year with four interceptions, two touchdowns and 56 tackles.
Seth Trachtman is a fantasy sports expert and diehard Kansas City Chiefs fan. He doesn't often Tweet, but when he does, you can find him on Twitter @sethroto.
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