NFL Free-Agent Signings 2015: Assessing Most Notable Deals to Start Offseason

Making a big splash in NFL free agency is a great way to excite fans, but it isn't always the best move for a franchise.

While many times a veteran addition can make the difference between an average team and a playoff contender, it can also create future problems in the salary cap as well as on the field if the two sides can't make a fit.

This year's free-agent period is just getting started, but we are already seeing the two extremes with the first set of signings. Here is a look at the most notable transactions so far with grades for each.

Ndamukong Suh, Miami Dolphins

There hasn't been a more heavily pursued free agent in recent years than Ndamukong Suh. The dominant defensive tackle was on the target list for just about every team, including his former team in the Detroit Lions.

In the end, he ended up signing with the Miami Dolphins for a deal worth as much as $114 million with about $60 million guaranteed, according to ESPN's Chris Mortensen.

Based on the numbers Suh has put up over the past few years, this certainly seems like a great deal:

Bleacher Report's Cian Fahey also notes how the defensive tackle uses more than just his skill set to succeed:

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If you go through Suh's sacks from 2014 you find a lot of 'second-effort' sacks. Motor never stops.

— Cian Fahey (@Cianaf) March 9, 2015"

Of course, Suh's impact goes beyond just the stat sheet. He uses his size and strength to take on blockers and clog up the middle, greatly improving the run defense for whichever team he is playing for at the time. 

Considering the Dolphins ranked just 24th in the NFL against the run this past season, it's clear this move will lead to a big improvement.

On the other hand, one thing you have to consider is the price tag. Grantland's Bill Barnwell examined how the contract will hurt the team in other areas:

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It’s good, of course, that the Dolphins are taking cap space that previously belonged to underperforming players and reallocating it to a superstar like Suh. The problem, though, is that you still have to replace those guys you’ve put on the street, and you don’t have that $18 million to work with in the process. [...]

That’s why I don’t know whether the Dolphins should have signed Suh. In a vacuum, Suh is a colossus who would make any team better. In this reality, the impact of adding Suh could be countered by how his contract leaves the Dolphins pencil-thin at three or four other spots on defense. 

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The cost will certainly set Miami back a bit, but Suh also has the ability to make everyone around him better. The attention he warrants from opposing offenses will free up linebackers to make plays, giving the entire unit a boost.

Although the signing isn't a perfect one, it is still an extremely good move for the Dolphins.

Grade: A-

Julius Thomas, Jacksonville Jaguars

Jack Dempsey/Associated Press

The Jacksonville Jaguars haven't won many games in the past few years, but they did win the sweepstakes for one of the top free agents on the market, according to Ian Rapoport of NFL.com:

Julius Thomas was heavily sought after this offseason thanks to his impressive work over the past two seasons with the Denver Broncos, totaling 24 touchdown catches in that stretch. With his size at 6'5", the pass-catcher has established himself as one of the top red-zone threats in the game.

As Adam Caplan of ESPN noted, this signing will be a big help for Blake Bortles in the coming year:

Of course, this will be necessary considering the young quarterback's struggles. As a rookie, Bortles struggled to the tune of 17 interceptions with just 11 touchdowns as he posted a 69.5 quarterback rating. This will be a major drop-off from playing with Peyton Manning.

While Thomas is clearly a talented tight end, it will be difficult for him to have the same type of impact in the offense as he had in Denver. He will also struggle to match his touchdown total when the Jaguars struggle to get anywhere near the red zone.

Considering the cost, it will be difficult for the tight end to live up to this contract.

Grade: B-

Randall Cobb, Green Bay Packers

Chris Graythen/Getty Images

While re-signing your own player doesn't really feel like it has the same impact of bringing in someone new, the Green Bay Packers should be very happy about bringing home Randall Cobb.

General manager Ted Thompson indicated earlier in the offseason his willingness to re-sign the 24-year-old player, telling Tyler Dunne of the Journal Sentinel, "It’s not a secret that we try to keep and maintain our own guys as much as possible. ...We’re trying to do that with Randall."

However, with Jordy Nelson already on the roster and Davante Adams showing potential, it didn't seem likely Green Bay would be able to afford to keep him around. Fortunately, Cobb decided to take the hometown discount and returned for $40 million over four years, according to Tom Silverstein of the Journal Sentinel.

As Dave Hyde of the Sun-Sentinel reported, the Miami Dolphins were willing to pay more to bring in the talented receiver. The Oakland Raiders were also in contention, and ESPN's Bill Williamson noted how disappointed the team has to be to lose out on Cobb:

Despite the chance to make more money, he apparently realized how enjoyable it is catching passes from Aaron Rodgers compared to less-established quarterbacks.

From the Packers' perspective, this becomes a huge transaction to remain one of the top offenses in the league. Field Yates of ESPN.com pointed out how good the week has been for Rodgers:

There are still holes elsewhere on the roster, but keeping Cobb at a reasonable price had to be the best-case scenario for the offseason.

Grade: A+

Note: For a full look at the NFL signings to this point, check out ESPN's tracker.

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