NFL Rumors: Latest on Michael Johnson, Terrance Knighton and Nick Fairley

Just in case you haven't picked up on this yet: The NFL free-agency market is fluid.

One moment, Chip Kelly is telling reporters the Eagles' decision to trade LeSean McCoy was about the salary cap. A day later, ESPN's Adam Schefter is reporting that Kelly has given DeMarco Murray a bigger contract than the one McCoy signed with Buffalo.

Perhaps the only thing that doesn't change from minute to minute is that no one has figured out what the hell Chip Kelly is doing with this Eagles roster. Everything else is in a massive state of flux, with commitments changing by the minute and more veterans being dumped onto the market as we speak.

It makes a process like this—updating the latest rumors around the league—much trickier. Words and phrasing change by the second, and sometimes things are scrapped altogether—the market is moving that fast.

With that in mind, let's not waste any more time. Here's a look at a trio of defensive linemen who are making waves on the open market (at least for now).

Michael Johnson to Meet With Vikings

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A year ago, Michael Johnson was one of the most coveted defensive players on the market. He signed a five-year, $43.75 million contract with the Tampa Bay Buccaneers, a deal that ostensibly tied him to the team for at least two years. Given the guaranteed cash on the table, it at least made sense on paper for Tampa to keep him through 2015.

Instead, the Bucs just decided to cut their losses, incurring a $7 million dead-cap charge to save right around $2 million.

It's a curious decision to say the least, but one that allows another team to perhaps swoop in and find value. Schefter reported the Minnesota Vikings will be the first of the teams offered a crack at signing Johnson:

The Georgia Tech product made 27 tackles and four sacks last season, the worst all-around numbers since his rookie year. Never an elite pass-rusher—a 2012 breakout in Cincinnati excepted—Johnson was a surprising minus against the run in Tampa. Pro Football Focus' run-stop percentage had Johnson tied for 20th among 4-3 defensive ends, while he ranked outside the top 30 in pass-rushing productivity.

In his final season with Cincinnati, Johnson ranked fifth in run stop percentage and was much closer to average as a pass rusher.  

If they can get him at a reasonable price, the Vikings would be smart to take a short-term flier here. Johnson is still only 28 years old, equipped with the size and skill set to help at a position at which Minnesota could sorely use them. He'd be an excellent complement to pass-rushing specialist Everson Griffen, who led the team in 2014 with 12 sacks.

Nick Fairley to Meet With Rams

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A year ago, the Rams doubled down on building through their offensive line by selecting Aaron Donald despite needs elsewhere. The move paid off, as Donald earned a Pro Bowl berth and Defensive Rookie of the Year honors.

With Chris Long due back at full health, Donald ascending and Robert Quinn continuing to terrorize backfields, it would seem St. Louis would stand pat on adding defensive line talent.

Not so, apparently. Ian Rapoport of NFL Network reported the Rams are hosting free agent Nick Fairley on Thursday:

Fairley, 27, is perhaps the most coveted defensive lineman remaining on the market. Slimmed down after a disappointing first three seasons, the Auburn product was well on his way to a career year before a knee injury knocked him out after eight games. PFF's metrics had Fairley ranked third in pass-rushing productivity and 14th in run-stop percentage before he went out of the lineup.

Adding that version of Fairley to that defensive line would be almost unfair; it would challenge or perhaps surpass the Buffalo Bills as the fiercest unit in football. 

Rick Osentoski/Associated Press

Of course, the problem with Fairley is knowing what's to come.

For his first three seasons, Fairley was at best forgettable and at worst a bust. The only reason he's on the market now is that the Lions thought so little of his production that they declined his fifth-year option.

Eight games of film and the looming aura of his "potential" is all teams have to claim that he's a productive NFL talent. There are 38 games of film that indicate Fairley is something much less than he showed in 2014.

I'm curious to see how teams handle the negotiations. Fairley's representatives will obviously emphasize the positives, noting his most recent sample of play. Teams would probably be smart to counter with his history of weight and effort problems, hoping to drive down the price.

Either way, even the potential of his landing in St. Louis is a scary prospect.

Terrance Knighton Drawing Interest in Baltimore

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Since signing in Denver on a cheap two-year, $4.5 million deal, Knighton has become something of a cult figure.

His "Pot Roast" nickname is one of the NFL's best, and its proliferation coincided with the best two-year stretch of football in Knighton's career. He made 61 tackles and five sacks with the Broncos, emerging as a run-stuffing fiend who can draw double-teams.

PFF ranked him solidly against the run and just fine in pass rushing, and his overall grades made him its 12th-best defensive tackle in football.

Knighton also doesn't turn 29 until July, putting him right in the range to get one last solid contract before his prime ends. According to Aaron Wilson of The Baltimore Sun, that deal may come from the Ravens.

Baltimore is looking for a replacement for the departed Haloti Ngata, who was traded to the Detroit Lions this week for draft-pick compensation. Ngata was dealt after prolonged negotiations in which the Ravens attempted to lower his cap number by signing him to an extension.

Knighton would probably fit right into plans as a relatively similar option—one who will save them money over the short and long term. He's also younger, which is something that will help Ozzie Newsome build toward the future amid other questions across the roster.

At the very least, the dude's nickname is Pot Roast. How can you go wrong?

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All contract info via Spotrac