It's hard to believe now, but 2014 was considered as a pivotal year for New England Patriots tight end Rob Gronkowski. Although he was the NFL's best tight end when healthy, he had missed 14 regular season games over the previous two years because of back, forearm and knee injuries.

The Patriots had until the last day of the 2015 league year to pay him a $10 million option bonus to pick up his 2016-19 contract years. Another injury-plagued season in 2014 could have forced a difficult decision on Gronkowski's future with the Patriots. It became a moot point after he caught 82 passes for 1,124 yard with 11 touchdowns that season.

A different set of players face a crossroads or have something to prove every year for a variety of reasons. The most common reasons are related to age, contract or salary cap concerns, injury, poor performance or off-the-field issues. Here's a player from each AFC team to keep an eye on during the 2016 season fitting into one of these categories.

Baltimore Ravens: Terrell Suggs

Suggs missed the last 15 games of 2015 after tearing his left Achilles in Baltimore's season opener. It was the second Achilles tear for Suggs after injuring his right one in 2012. He rebounded from the initial tear to earn the sixth Pro Bowl berth of his career in 2013. It remains to be seen whether the 33-year-old can bounce back as effectively this time around.

Buffalo Bills: Tyrod Taylor

Taylor is the NFL's lowest-paid starting quarterback that isn't on a rookie contract after he unexpectedly won a three-way quarterback competition with 2013 first-rounder EJ Manuel and Matt Cassel last preseason. His two-year contract has a base value of $2.15 million.

The first-time starter emerged as one of the NFL's best dual-threat quarterbacks in 2015. Taylor was second in rushing among quarterbacks with 568 yards and seventh in the NFL with a 99.4 passer rating.

Taylor had a great first season as starter, but can he do it again? USATSI

The Bills have been reluctant to give Taylor, who is in a contract year, a new deal worthy of QB1 status because of his limited track record. A repeat performance could bring a non-exclusive franchise tag into play next year. The quarterback number should be approximately $21.4 million in 2017 with a salary cap in the neighborhood of $168 million.

Cincinnati Bengals: Jeremy Hill

Hill must rebound from a sophomore slump for Cincinnati to earn a sixth consecutive playoff berth in the highly competitive AFC North. He only averaged 3.6 yards per carry, and his 1.46 yards after contract was fourth worst in the NFL.

The 2014 second-round pick was phenomenal as a rookie. Hill's 5.1 yards per carry was third among NFL running backs in 2014. He was also second in the NFL in rushing during the second half of the 2014 season with 775 yards.

Cleveland Browns: Robert Griffin III

Robert Griffin III signed a two-year, $15 million deal (worth up to $22 million with incentives) with Cleveland to try to resurrect his career. The situation sets up nicely on paper for the 2012 NFL Offensive Rookie of the Year because USC's Cody Kessler wasn't taken until late in the third round (and was widely considered a reach) despite speculation that a quarterback would still be taken with the team's first pick even after trading down from No. 2 overall. Griffin may not get another shot at being a starting quarterback if he can't beat out 36-year-old journeyman Josh McCown, Austin Davis and Kessler during training camp.

Denver Broncos: Mark Sanchez

Sanchez was given a new lease on his NFL life when he was quickly obtained from the Philadelphia Eagles for a conditional 2017 seventh-round pick after Brock Osweiler left for Houston. As the only quarterback on Denver's roster with any significant game experience, Sanchez should have the inside track to start.

Sanchez merely performing like an average starting quarterback will likely give the Broncos a legitimate chance to repeat as Super Bowl champions, because the defense should remain dominant despite some key losses in free agency.

Houston Texans: Jadeveon Clowney

Injuries are a big part of why the 2014 first-overall pick hasn't made the impact the Texans have expected. Clowney has missed 15 regular season games during his two NFL seasons. He was also unavailable for the Texans' playoff loss to the Kansas City Chiefs last season.

Clowney becomes even more pivotal if Watt misses time. USATSI

Clowney staying on the field takes on more importance because of J.J. Watt's back surgery. In a best case scenario, Watt will be ready for the season opener against the Chicago Bears, but it wouldn't be a surprise if Watt didn't make his season debut until early October.

Indianapolis Colts: Andrew Luck

2015 was a season to forget for Luck. Assorted injuries contributed to him having the worst season of his four-year NFL career, and at 8-8, the Colts missed the playoffs for the first time since making him the first-overall pick of the 2012 draft. When Luck's season ended after a Week 9 victory over the Broncos because of season a kidney laceration and abdominal tear, he ranked 31st in completion percentage (55.3 percent) and 32nd in passer rating (74.9). Luck had also thrown the second most interceptions (12) in the NFL.

This didn't stop the Colts from signing him to a five-year, $122.97 million contract extension containing $87 million in guarantees, which makes him the NFL's highest-paid player. Luck will need to consistently perform at the same level or better than he did in 2014 to live up to his lofty contract. In 2014, he led the NFL with 40 touchdown passes and was third in passing yards (4,761) and seventh in passer rating (96.5).

Jacksonville Jaguars: Luke Joeckel

Joeckel was supposed to anchor Jacksonville's offensive line when he was taken with the second-overall pick in the 2013 NFL Draft. Instead, the Jaguars declined to pick up Joeckel's fifth year option in 2017 for $11.902 million.

Kelvin Beachum, who is coming off of a torn left ACL, was given a one-year deal for $5 million with an option for $40 million over four years (worth up to $50 million through salary escalators) to provide competition for Joeckel at left tackle. If Joeckel can't hold off Beachum, a move to left guard could be Joeckel's last chance to impress general manager David Caldwell and head coach Gus Bradley.

Kansas City Chiefs: Jamaal Charles

Surprisingly, the Chiefs won 11 straight games, including the playoffs, with Spencer Ware and Charcandrick West operating in Charles' place after he suffered the second ACL tear of his career five games into the 2015 season.

Ware and West signing identical three-year, $4.2 million deals (worth a maximum of $8.2 million with salary escalators) suggests that the Chiefs have a succession plan in place at running back. 2016 will likely be the last season in Kansas City for Charles, who turns 30 in December, if he doesn't return to form with two reconstructed knees.

Miami Dolphins: Ryan Tannehill

The eighth-overall pick in the 2012 draft has yet to have a true breakout year, but Jay Cutler thrived in 2015 with new Dolphins head coach Adam Gase during his lone season as the Chicago Bears' offensive coordinator.

Tannehill may need a big season to stay Miami's quarterback. USATSI

It's conceivable that the Dolphins could look for a new quarterback in 2017 if the same doesn't happen with Tannehill. Only $3.5 million of Tannehill's $17.975 million 2017 base salary is fully guaranteed, and the remaining $14.475 million becomes fully guaranteed in mid-March on the fifth day of the 2017 league year.

New England Patriots: Jimmy Garoppolo

Garoppolo will be under the microscope while Tom Brady serves his four-game suspension in connection with Deflategate to begin the season. Keeping the Patriots on track during the first four starts of his career could pay big dividends for the 2014 second-round pick. The Patriots would likely have a valuable trade commodity for any quarterback-needy team looking for a starter.

New York Jets: Ryan Clady

Clady (along with a 2016 seventh-round pick) was acquired by the Jets from the Broncos in April for a 2016 fifth-round pick. He'll replace D'Brickashaw Ferguson, who retired instead of taking a pay cut. Clady reworked his contract in the process to lower his 2016 salary from $9.5 million to $6 million with another $1.5 million in incentives. The Jets hold an option on Clady in 2017 that requires a $1 million payment to pick up his $10 million salary.

Clady was an elite left tackle prior to missing a majority of the 2013 season with a Lisfranc foot injury and the 2015 season with a torn ACL in his left knee. An inability to play at a similar level as before the injuries likely means New York will be just a one-year pit-stop for Clady.

Oakland Raiders: Latavius Murray

It was a tale of two seasons for Murray, even though he became Oakland's first 1,000-yard rusher since Darren McFadden in 2010. Murray was less effective as the season progressed. 436 of his 1,066 rushing yards came in the first eight games of the season, and he went from 4.8 yards per carry in the first half of the season to 3.3 over the last eight games.

Murray is in the final year of a $2,226,200 rookie contract. The $6.5 million annual salary with $14 million fully guaranteed Lamar Miller received from the Texans could become Murray's salary floor on his next contract, provided he consistently performs more like he did when rushing for 632 yards on 132 carries in the first half of the 2015 season.

Pittsburgh Steelers: Le'Veon Bell

Bell is confident he won't serve the four-game suspension to start the season he is facing under the NFL's substance abuse policy for allegedly missing multiple drug tests. Absent a compelling reason or extenuating circumstances, winning these types of appeals is extremely difficult.

Bell's 2015 season was derailed by a torn MCL and PCL in his right knee during Week 8's game against the Cincinnati Bengals, which sidelined for the rest of the season. He was also suspended for the first two games because of a substance abuse violation.

Bell is one of the NFL's best backs when on the field. USATSI

Although Bell is the NFL's best dual-threat running back when healthy, a long-term contract at market value could be in jeopardy unless he can start erasing any concerns the Steelers may have about his reliability. Assuming Bell's appeal is unsuccessful, his next offense could bring about a one-year ban, or 10 games instead with a positive test for marijuana.

San Diego Chargers: Melvin Gordon

The Chargers need Gordon to take a step forward to provide much-needed offensive balance after Philip Rivers led the league by throwing a career-high 661 passes in 2015. Gordon's disappointing rookie campaign included just 641 yards on 184 carries and ball security issues. His five fumbles tied him for the second most in the NFL on rushing attempts.

Gordon, who had microfracture surgery on his left knee, found a mentor in Adrian Peterson. Hopefully, the second-year player's time with the future Hall of Famer was well spent.

Tennessee Titans: DeMarco Murray

Murray was one of 2015's most disappointing free agent signings after receiving a five-year, $40 million contract (with $21 million in guarantees and worth a maximum of $42 million through salary escalators) from the Eagles. He gained 702 yards, the second-worst total in his five NFL seasons, on a career low 3.6 yards per carry.

Murray was traded to the Titans early in the offseason in an exchange of 2016 fourth-round picks. He cut $5.45 million out of the remaining four years of his contract to make the deal work. He needs to be a lot more effective than he was last season because 2015 Heisman Trophy winner Derrick Henry, who was taken in the second round, is waiting in the wings.