NFL: Preseason-San Francisco 49ers at Denver Broncos
Ron Chenoy / USA TODAY Sports

Ten offensive players to keep an eye on were covered in an article earlier in the week. The focus now turns to the other side of the ball.

Every season, a different set of players face a crossroads or have something to prove 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.

Below are 10 defensive players to keep watch during the 2021 season who fit into one of those categories.

Von Miller, OLB, Broncos

Miller missed the 2020 season because of an ankle injury requiring surgery. The Super Bowl 50 MVP was coming off a down 2019 by his standards. His eight sacks were his lowest total in playing a full season. Miller, who is 32 and in a contract year, balked when the Broncos asked him take a pay cut in advance of the decision to pick up the option on his 2021 contract year worth $18 million. Since it will cost $26.45 million for the Broncos to designate Miller as a franchise player in 2022, he seems destined to hit the open market for the first time his 10 year NFL career.

Stephon Gilmore, CB, Patriots

Gilmore skipped June's mandatory minicamp because of dissatisfaction with his contract. His unhappiness dates back to last season when the Patriots raised his 2020 salary since he was clearly outperforming his contract after being named 2019's NFL Defensive Player of the Year. In turn, Gilmore's 2021 total compensation was reduced from $12 million to $7,911,765.

Gilmore, who is in a contract year, is out for at least the first six games of the regular season after being placed on the physically unable to perform list at the final roster cutdown because of a partially torn quad that required offseason surgery. There hasn't been any progress made on Gilmore's contract as he is still scheduled to play for the reduced amount.

Gilmore, who is 31, will likely be auditioning for other teams when he returns since signing him to an extension given his age would be a departure from the "Patriot Way". Under long-time head coach Bill Belichick, the "Patriot Way" has been to get rid of a player a year too early rather than a year too late whether it's because of salary, performance or age.

Chandler Jones, EDGE, Cardinals

The Cardinals have gotten their money's worth from the five-year, $82.5 million deal Jones signed after he was designated as a franchise player in 2017. Since signing the contract, Jones' 50 sacks are the second most in the NFL behind only Rams All-Pro defensive tackle Aaron Donald's 57.5 despite missing the final 11 games last season with a torn biceps.

Jones requested a trade during the offseason when it became apparent the Cardinals weren't going to address his contract. He is in a contract year. The Cardinals have no intention of trading him.

Jones surely took note of the Cardinals making wide receiver DeAndre Hopkins the NFL's highest paid non-quarterback at $27.25 million per year last preseason with three years remaining on his contract before he had played a down of football for the team. Paying another outsider before him, J.J. Watt, likely was rubbing more salt in the wound. Watt signed a two-year, $28 million contract (worth up to $30 million through incentives and salary escalators) after the Texans granted his request to be released.

It's going to be cost prohibitive to use a franchise tag on Jones during next offseason. His franchise number projects to $25 million.

Excited for the biggest NFL schedule in history? Follow along on the CBS Sports app and get the latest insights from our team of NFL insiders, plus news from our team of experts, as well as data insights on every player. If you already have the CBS Sports app, make sure to favorite the your favorite team so you don't miss a thing!

Derwin James, S, Chargers

James was a first team All-Pro as rookie in 2018. He's only played five games since then. James missed the entire 2020 season because of a torn meniscus in his right knee. Nonetheless, the Chargers picked up a fifth year option for James in 2022 worth a fully guaranteed $9.052 million. Should James stay on the field this season, he could be in a position to reap the benefit of Jamal Adams dramatically resetting the safety market with the four-year, $70 million contract extension he recently received from the Seahawks.

C.J. Mosley, ILB, Jets

Mosley has yet to make an impact for the Jets since fundamentally changing the off ball linebacker market with the five-year, $85 million contract he signed in 2019 free agency. The deal contained $51 million of guarantees where $43 million was fully guaranteed at signing.

Mosley only played two games in 2019 due to a groin injury. He opted out of the 2020 season because of the COVID-19 pandemic, which caused his contract to toll. This means Mosley's 2020 contract year became his 2021 contract year and the additional years in the contract were also pushed back one year.

Even if Mosley can't justify his contract through his play this season, he'll probably still be around in 2022. Mosley's $16 million 2022 base salary became fully guaranteed in March 2020. It was originally Mosley's 2021 base salary before his contract tolled with the opt out.

Jadeveon Clowney, EDGE, Browns

Clowney couldn't find any takers in 2020 free agency at his original asking price, which was reportedly over $20 million per year, because of a lack of sacks during the 2019 season and a core muscle injury that required surgery. He signed a one-year deal for $13 million (worth up to $15 million through incentives) with the Titans to reunite with Mike Vrabel right before the 2020 regular season started. The Titans head coach was Clowney's defensive coordinator with the Texans in 2017 and linebackers coach for the three seasons before.

Clowney was sackless in the eight games he played in 2020 before season ending surgery to repair a torn meniscus in his left knee. He still managed to get a one-year, $8 million contract year worth a maximum of $10 million with incentives from the Browns. Double teams will be few and far between for the three-time Pro Bowler playing opposite All-Pro Myles Garrett on Cleveland's defensive line. If Clowney can't thrive under these circumstances, the big payday he has been seeking may permanently elude him.

Landon Collins, S, Washington

The structure of Landon Collins' contract has been his saving grace since 2020 seventh round pick Kamren Curl emerged at strong safety after he tore his left Achilles seven games into last season. The proration from the Collins' $15 million signing bonus and $6 million option bonus as well as the guarantees with his $12.5 million 2021 base salary made it difficult to release him. $5 million of the $12.5 million, which was guaranteed for injury at signing, was fully guaranteed upon execution of the contract. The remaining $7.5 million was fully guaranteed on March 21, the fifth day of the 2021 league year.

Collins has made a faster than expected recovery from the Achilles. He'll need to keep it that way in order to have a chance at being in Washington next year. Collins is scheduled to make a non-guaranteed $12 million in 2022 while Curl's salary is $895,000.

Leighton Vander Esch, LB, Cowboys

Picking up Vander Esch's fifth year option was already a risky proposition before the Cowboys selected Micah Parsons with the 12th overall pick in the 2021 NFL Draft because of durability concerns dating back to his collegiate days at Boise State. Drafting Parsons made declining the $9.145 million option much easier. Vander Esch is on the verge of becoming Dallas' new Sean Lee, a talented linebacker who has trouble staying healthy.

Jaylon Smith, LB, Cowboys

Smith has been a disappointment since signing an extension in 2019 where he gave up five unrestricted free agent years valued at $12.8 million per year. Keanu Neal making a seamless transition from safety to linebacker in joining his former Falcons head coach Dan Quinn, who is Dallas' new defensive coordinator, could limit Smith's playing time. Unless Smith elevates his level of play, he'll be released next offseason before his $9.2 million 2022 base salary, which is guaranteed for injury, becomes fully guaranteed next March on the fifth day of the 2022 league year. The Cowboys will pick up $5 million of 2022 salary cap space with Smith's departure, which would leave a $6.8 million cap charge.

Anthony Harris, S, Eagles

A soft free agent market led to Harris taking a one-year "prove it" deal for $4 million with an additional $1 million in incentives from the Eagles. It's a significant pay cut for Harris, who played the 2020 season for the Vikings under an $11.441 million franchise tag. The Vikings kept Harris from hitting the open market after a stellar 2019 season in which he tied for the NFL lead with six interceptions. Harris will need to play like he did in 2019 to have any shot at getting close to the same salary stratosphere as Harrison Smith, his former Vikings teammate. Smith, who is 32, just signed a four-year extension averaging $16 million per year to become the NFL's second highest paid safety.