The NFL's 2015 contract year superstars

In the NFL, as in other sports leagues, it's important to take note of players entering the "contract year," or final season under their current deals. The prospect of an uncertain future can have a significant impact on the way players conduct themselves, whether they take a more cautious approach to potential injuries or lay it all out in an attempt to convince a team to invest heavily in them during the following offseason.

Not all players entering contract years are equal. For example, established quarterbacks, often the centerpieces of their respective franchises, hold most if not all the leverage in their negotiations. Conversely, an established running back in the same position will often be made to play the year out without meaningful discussion about a contract extension.

Another common narrative is the underachiever who comes alive during their contract year. While many of these breakout seasons prove to be more than just a flash in the pan, cautionary tales like Albert Haynesworth (8.5 sacks in 2008, 6.5 the rest of his career combined) have colored the perception of these types of players.

So which contract year players deserve your attention? Our list pulls from all categories.

Players with leverage

Philip Rivers

Through the first six weeks of the 2014 season, San Diego Chargers quarterback Philip Rivers might have been the best player in the league. Over that span, he tossed 15 touchdowns against only two interceptions. Combined with his other passing numbers, Rivers produced a passer rating of 117.6.

However, as his offensive line disintegrated around him (the Chargers went through five different centers), Rivers eventually succumbed to a back injury. Though he never missed a start, the quarterback finished each of his last four games with a sub-90 passer rating.

Regardless, Rivers is considered one of the best signal callers in the league, which is why the Chargers are understandably concerned about his refusal to sign an extension before the upcoming season. While the team can apply the franchise tag to Rivers, it's difficult if not impossible to build a contender around a quarterback who wants to leave town. Accordingly, if Rivers asks for $20 million or more in annual salary, the Chargers have little choice but to pay it.

Justin Houston

While J.J. Watt has rightfully garnered the title of best defensive player in the NFL, Justin Houston isn't too far behind. Through four seasons, the Kansas City Chiefs linebacker has compiled an impressive 48.5 sacks, including 22 a year ago. Houston has also developed as a turnover producer, forcing seven fumbles and recovering five live balls during his Kansas City career.

This offseason, the salary cap-strapped Chiefs placed the franchise tag on Houston in order to prevent his departure. However, though the All-Pro will play this season in Kansas City, he becomes even more costly to franchise in 2016. With another big season, Houston can demand the largest contract for a defensive player in league history, topping the one signed by Ndamukong Suh in March.

Dez Bryant/Demaryius Thomas

Two of the best wide receivers in football both hit free agency this offseason. Both also received the franchise tag and, barring long-term extensions, will become free agents again a year from now.

Dez Bryant is coming off his third consecutive season of over 1,200 receiving yards and double-digit touchdowns. Demaryius Thomas, meanwhile, has hauled in 10 touchdowns or more each of the last there seasons but has also registered no fewer than 1,430 receiving yards in any of those years. Though both wideouts benefit from the presence of superstar quarterbacks Tony Romo and Peyton Manning, there is plenty of reason to believe they can continue to produce in different settings.

At the moment, no extension announcement appears imminent for either player. If they make it through 2015 without signing new deals, the cost to retain them in 2016 will go up significantly.

Marshal Yanda

Without much fanfare, Marshal Yanda has established himself as one of the best offensive linemen in football in recent years. The Baltimore Raven has earned four straight Pro Bowl nods as well as All-Pro honors in 2014. Just as importantly, Yanda rarely misses a game. Over the last five seasons, he played 78 out of possible 80 games. Though primarily a guard, Yanda has also shifted over to right tackle to cover for an injured teammate.

In most cases, it would be easy to assume the Ravens would simply re-sign their All-Pro and move along. However, Yanda's teammate Kelechi Osemele also hits free agency next year. Though not as talented as Yanda, Osemele is five years younger and can also play guard or tackle. If forced to choose between the two, GM Ozzie Newsome might lean towards youth.

Trent Williams

One of the best left tackles in the league, Washington's Trent Williams will see his contract expire after the upcoming season. He possesses the size (6'5, 315 pounds) and skillset to fit into any offense, making him an expensive asset to secure past 2015.

Teams rarely allow franchise left tackles to depart, and Washington probably won't even give him the chance. If the two sides cannot come to an agreement on a long-term extension, the franchise tag could be in Williams' future. Still, stranger things have happened in the NFL, and Williams may be special enough to convince another team on the brink of a championship to pony up two first-round picks in order to lure him away from the nation's capital.

The underachievers

Sam Bradford

After back-to-back season-ending knee injuries and an overall disappointing career in St. Louis, the Rams traded Sam Bradford to the Philadelphia Eagles for Nick Foles and draft pick consideration. Bradford, the No. 1 overall pick in 2010, returns to an aggressive, up-tempo offense led by head coach Chip Kelly. The trade also represents a reunion of sorts with Pat Shurmur, Bradford's offensive coordinator during his best season in St. Louis.

The biggest obstacles for Bradford (other than staying on the field) will be his decision making and accuracy. Kelly's offense requires quarterbacks to make quick reads and respond accordingly. Bradford, entering his sixth season in the league, hasn't always displayed the best reaction time as plays developed. Similarly, he'll need to connect on more of his passes, especially downfield. Bradford's career completion percentage stands at 58.6. While Kelly's offense won't task him with as many difficult throws as Brian Schottenheimer's did in recent years, Bradford must improve on 35.4, his career completion percentage on pass attempts targeted 20 or more yards down the field.

Justin Blackmon

Since being selected with the No. 5 overall pick in 2012, Justin Blackmon has caught just 93 passes for 1,280 yards and six touchdowns. That production isn't the result of ineffective play, however. Rather, Blackmon hasn't managed to stay off the NFL's discipline radar since entering the league. Out of 48 possible games, Blackmon has played in just 20. His status for the 2015 season has yet to be resolved, though it appears he will return at some point during the upcoming season.

Much like Josh Gordon, few around the league question Blackmon's talent level. He's a big-bodied receiver who can make difficult catches and run through defenders. Of course, he needs to stay on the field in order to continue his career. With the Jacksonville Jaguars investing multiple draft picks at the wide receiver position, it appears Blackmon's days in Jacksonville are numbered. A good showing on and off the field in 2015 might convince another team to invest a multi-year contract in the Oklahoma State product.

Nick Perry

Nick Perry has struggled through injuries and a poor scheme fit since entering the league in 2012. Perry, a 271-pound defensive end when he showed up at the combine, was selected by the Green Bay Packers and made to play outside linebacker in the team's 3-4 base defense. While the defensive-end-to-linebacker transition isn't an uncommon one, Perry's size and lateral movement skills made him an odd candidate.

To his credit, Perry has shown flashes at his new position and provided some productivity as a pass rusher. However, he has missed time each season to injury and hasn't registered more than four sacks in any given season.

Perhaps Perry's best bet is to show enough skill in 2015 that a 4-3 team brings him in to play defensive end, à la Jerry Hughes in Buffalo.

Eric Berry

It's not really fair to place Eric Berry, a three-time Pro Bowler and first-team All-Pro, in the category of underachievers. His play has simply been too good to share column space with the likes of Bradford, Blackmon and Perry. However, an ongoing battle with Hodgkin's Lymphoma has clouded Berry's future in the NFL.

Should Berry return to the field in 2015 and show the same high level of play, a new contract will surely follow. However, the Chiefs have made no indication as to when the safety will be cleared to play.

Russell Okung

The Seattle Seahawks' Russell Okung hasn't underachieved in terms of on-field performance; the former Oklahoma State standout has proven himself as one of the league's most capable left tackles in that regard. However, injuries continue to define Okung's career, and another season of multi-game absences will significantly affect his market come the 2016 offseason.

Through five years in Seattle, Okung has yet to put together a full 16-game campaign. He came close in 2012, starting 15 contests and earning his first trip to the Pro Bowl. His health struggles have gotten the better of him over the last two seasons as Okung has missed 10 starts.

Okung's situation shares plenty of similarities with that of Packers right tackle Bryan Bulaga a year ago. A fellow 2010 first-round pick, Bulaga missed roughly half of the 2012 season to a hip fracture along with all of 2013 to a torn ACL. However, he returned to Green Bay's starting lineup last season and started 15 regular season games, reclaiming his pre-injury form in the process. Bulaga was awarded a five-year, $33.75 million deal this offseason as a result. If Okung stays healthy in 2015, he could see even bigger dollar signs a year from now.

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