NFL Free-Agent Signings 2015: Moves That Will Make Biggest Impact

Free agency in the NFL began on March 10, but so far trades have made the biggest news. While it isn't everyday all-pro tight ends like Jimmy Graham are traded, the lack of free-agent buzz is partly due to NFL teams slapping the franchise tag on quite a few of the most notable and eligible players.

The Dallas Cowboys franchised Dez Bryant. The Denver Broncos went the same route with Demaryius Thomas, and the Kansas City Chiefs protected themselves by franchising Justin Houston. Those players are likely to return to their old teams for at least one more season, but not everyone was franchised.

Here's a look at three signings that will have the biggest impact in the upcoming season.

Ndamukong Suh, Miami Dolphins

During the lead-up to free agency, Ndamukong Suh was viewed as the top free-agent target. The Miami Dolphins wasted no time making the all-pro defensive tackle an offer he couldn't refuse. The $114 million deal makes Suh the highest-paid defensive player in history.

It also gives Miami one of the fiercest defensive lines in the NFL.

The Dolphins already have the productive, but aging Cameron Wake and young and improving Olivier Vernon. Between Suh, Wake and Vernon, the trio amassed 26.5 sacks in 2014.

Suh's presence on the inside should provide a balanced pass rush and above-average run stuffing up the middle. The pieces are in place for the Dolphins to have one of the premier defenses in the NFL in 2015.

Devin McCourty, New England Patriots

Simply put, McCourty has blossomed into one of the best ball-hawking safeties in the NFL. Because he's just 27 years old, the New England Patriots were smart to re-sign him to a five-year, $47.5 million deal.

The defending champions have struggled to find mainstays in their secondary, and McCourty has proven to be elite at his position. Though seemingly undersized at 5'10", 195 pounds, McCourty has been durable.

He's only missed three games in his five-year career. Over that time he has 17 interceptions. Bringing him back was a must for New England.

Julius Thomas, Jacksonville Jaguars

USA TODAY Sports

Slowly but surely, the Jacksonville Jaguars are putting the pieces in place to have a respectable offense. Second only to a strong running game, a dependable pass-catching tight end is the best weapon a young quarterback can have.

Thomas will be just that to second-year Jaguars quarterback Blake Bortles. 

From 2013-14, Thomas averaged 5.6 receptions per game, and he's had 12 touchdown catches in each of the last two seasons. Per Ian Rapoport of NFL.com, the Jags are throwing a large amount of money Thomas' way.

Jacksonville has been taking baby steps toward respectability the last few years. This move was perhaps its first giant step in the right direction. A tight end doesn't transform a team from a cellar dweller to a Super Bowl contender, but this is a good move.