Every year, a key free-agent acquisition or draft pick plays a pivotal role in their team's run toward the postseason.
From Reggie White moving from Philadelphia to Green Bay in 1993 to Drew Brees signing with the Saints and leading them to the first Lombardi Trophy in franchise history, free agency has changed the way organizations go about building their roster.
Entering the 2012 NFL season, there are 10 moves that may prove to be the difference between a team taking a step forward or coming back to the pack. Here's a look at these potential game-changing moves and what these players, coaches and general managers can offer their new teams.
Wimbley has racked up 16 sacks over the last two seasons, including seven in 2011, and joins a defensive front four that failed to consistently pressure the quarterback last season.
The Tennessee Titans starting defensive ends combined for 5.5 sacks in 2011, the fewest of any base 4-3 defense team in the league. After losing one of its starters in Jason Jones to Seattle, the Titans bring in Wimbley in the hope that he can get to the passer and open things up for the other defensive lineman.
Wimbley, who has served as a pass-rushing outside linebacker and as a lineman throughout his career, will become a full-time defensive end in 2012, where he will be asked to lead one of the youngest defensive units in the league.
After spending the first seven years of his career in San Diego, Jackson will look to bring his enormous playmaking abilities to a Buccaneers offense that really struggled to put points on the board last year.
This offseason, Tampa Bay made an effort to surround fourth-year quarterback Josh Freeman with talent after the 24-year old posted a career-high 22 interceptions in 2011. Jackson is the kind of target Freeman needs, as he has great size and athleticism that enables him to go up and make plays both downfield and in the red zone.
Jackson will join former Saints guard Carl Nicks and longtime Colts tight end Dallas Clark in Tampa Bay, as new head coach Greg Schiano looks to rebuild a Buccaneers team that is just two years removed from a 10-6 season.
Since the departure of Randy Moss, the Patriots passing offense has been based around playmaking tight ends and underneath routes to Wes Welker.
Lloyd, though not as talented as Moss, brings a similar skill-set to the table and has the hands and route-running ability to give Tom Brady yet another option downfield.
It is of little surprise to anyone that Lloyd ended up with New England, where he pairs up yet again with offensive coordinator Josh McDaniels, who coached Lloyd during his years with the Broncos and Rams.
Lloyd's ability to go up and grab the ball at its highest point gives Brady the deep target on the outside that can make the already dangerous Tom Brady all the more deadly for opposing defenses.
Fisher's tenure with the Tennessee Titans is well documented. Although the two parties had a less than cordial split after the 2011 season, Fisher went to the playoffs six times in 17 years on his way to becoming the longest-tenured coach in the league.
Though Fisher has not had the playoff success one would expect from his vast amount of experience as a head coach, over the years he has proven that he can get the most out of the talent placed in front of him, a skill that will be needed as the St. Louis Rams continue to rebuild.
Fisher's presence has already worked wonders for the Rams, who were able to lure Cortland Finnegan, Scott Wells and Kendall Langford to fill some glaring holes on their depth chart.
After focusing much of their attention on the offense this offseason, the Broncos brass was able to bring in one of the brighter defensive minds in the game in Del Rio.
Though his message seemed to be getting a little stale toward the end of his years with the Jacksonville Jaguars, the defenses Jacksonville put on the field during his first few years with the team were known for their physicality and athleticism.
Del Rio will be tasked with forming a defense that is able to get the Peyton Manning-led offense onto the field as often as possible.
Though just a rookie, Luck brings a knowledge of the game that is matched by very few quarterbacks in the league.
With a new coaching staff and a young roster, Luck will be given the task of building chemistry with an offensive line that has been predominantly blocking for one of the best quarterbacks in the league.
Luck has a good arm and knows how to read the field, two things that are crucial to early success in the NFL. With veteran wide receiver Reggie Wayne returning as well as a Stanford connection at tight end in Coby Fleener, Luck has more receiving options than most first-round quarterbacks and will have the opportunity to establish himself as a franchise quarterback from day one.
The Raiders' struggles under former owner/general manager Al Davis have been discussed at lengths over the years.
McKenzie has been given the duty of assembling a roster that can bring Oakland to the playoffs for the first time since its Super Bowl appearance in 2001.
Though just one offseason into his tenure, the philosophical changes under McKenzie have already become apparent. Opting to go with solid additions rather than the flashy acquisitions of the past, McKenzie appears to want to build around a strong defense and an elite running game.
Any time you hand out one of the richest contracts in league history, you are expecting immediate production.
Williams' physical skills speak for themselves, and the fact that he is still just 27 years old indicates that he still has plenty of good football in front of him, but at times, his production in Houston has not matched his impressive measurables.
Through his first six years in the league, Williams has tallied 53 sacks and should provide both a pass-rushing threat on the edge while also taking the pressure off of the linebackers and the rest of the defensive line that Buffalo is building around.
Brandon Marshall has been one of the most consistently productive receivers in the NFL over the last five seasons.
In Chicago, Marshall is reunited with former Broncos quarterback Jay Cutler, with whom he had three of the most productive years of his career.
Marshall's presence in Chicago will allow Devin Hester the opportunity to see limited snaps, hopefully enabling him to become the playmaker that Bears fans know he is capable of being.
Marshall gives Cutler the first true No. 1 wide receiver that he has had since leaving Denver and opens up the field for one of the best running backs in the league in Matt Forte.
Many have questioned the amount of money Denver spent to bring in Peyton Manning, but one thing is certain, this one addition changed everything about the Broncos offense.
Coming off of a playoff appearance behind an offense built around pounding the football with Tim Tebow, Manning brings shades of his Colts system to Denver, which relies on primarily shotgun formations and chemistry between Manning and his receivers.
Though he missed all of last season, Manning's mind remains just as sharp as ever. One of the most cerebral quarterbacks in the history of the game, Peyton should prove to be effective at drawing safeties out of the box for the running game and opening up the field for his targets.