Five hundred and two. That’s the number of NFL players who spent time on the injured reserve in 2017 alone, meaning they sustained an injury severe enough that it caused them to miss the entire season, or at least the first eight weeks in some specific cases.

But that just scratches the surface of the number of players who are injured during a given season.

The amount of players who suffer injuries that are not severe enough for the injured reserve list combined with those who elect to not report their injuries at all dwarfs the mere 502 placed on injury reserve. It is virtually impossible to find a player who can tell you they went through an entire season and remained healthy throughout. The level of brutality in this sport is unmatched.

The irreversible damage this brutality does to the players’ bodies is well documented. But the financial implications these injuries have can be just as detrimental to the players’ lives. The average NFL career length is just over three years. Many of these short lived careers are brought to an early halt due to injury.

No one is more aware of this volatility in football than former Texas Longhorn and current Seattle Seahawk safety Earl Thomas, which led to his now infamous holdout and subsequent injury.

In a split second, one hit or one wrong pivot could derail a player’s entire life. Hence why players like Earl Thomas elect to hold out when they feel their level of financial compensation and security does not match what they are risking every time they step foot on that field.

Thomas saw the 502 lives that football forever changed during last season, but this was nothing new to him. He belonged to the same group of unfortunate players just a year prior.

Thomas used to be one of the most durable players in the NFL. He started the first 107 games of his career. That’s nearly seven full seasons. This streak was snapped whenever Thomas collided with fellow Seahawks safety Kam Chancellor and suffered a broken tibia during a matchup with the Carolina Panthers in 2016.

The worst case scenario that goes through an NFL player’s head every day came to fruition for Thomas. Shortly after the game concluded, he took to Twitter and spoke of a potential retirement from the NFL following the season-ending injury. He did not end up retiring, but he landed on the injured reserve list, concluding his 2016 season and changing his career forever.

Thomas’ next season did not end via injury, yet it would affect his career just the same.

2017 was another rough year for the “Legion of Boom,” to say the least. On Nov. 9, 2017, Richard Sherman tore his Achilles tendon and Chancellor suffered a neck injury against the Arizona Cardinals. It was during this game that Sherman and Chancellor became part of the 502. That is the day the Legion of Boom died.

That was the last game that Sherman would play in a Seattle Seahawks uniform, signing with the San Francisco 49ers last offseason. For Chancellor, it was likely the last football game he’d ever play, retiring later that year due to the possibility of further injury.

Enter summer 2018. As one of the best safeties in the NFL, Thomas recognized his value and the fact that he wasn’t being compensated as such. But it wasn’t just his status as the best that made him want this extension.

If that were the case, Thomas could have easily played out the final season of his contract and signed a well-deserved extension in the following offseason. After what he saw happen to the Legion of Boom in the previous 18 months, Thomas did not want to risk walking onto an NFL field again without having long-term financial security.

The only problem is the Seahawks had no intention of giving him this extension, for many of the same reasons he wanted it. And thus began the holdout.

Thomas failed to report to any of the team’s offseason activities. His relationship with the team was on thin ice for much of the summer.

“I’m asking the Seahawks to do one of two things: Offer me an extension,” Thomas wrote in an article for the Players’ Tribune. “Or trade me to a team that wants me to be part of their future.”

The ultimatum was set. Thomas made it clear he was done negotiating.

His holdout continued into training camp as he stayed apart from the team until the week before the start of the regular season. Being fined heavily each week, he decided to rejoin his teammates on Sept. 5. Despite the clear message he had sent, Thomas would once again play for the Seahawks — without an extension. The organization had officially won the holdout.

Thomas would then begrudgingly honor his contract and play out the season as the leader of the Seahawks defense, hoping for a midseason trade or at the very least, to finish the season in good health and enter free agency unimpeded.

His season began as well as one could hope for, as he finished the first three games with three interceptions. He was still showing that he was the league’s best safety. But his fortune turned for the worst in the fourth week of the season when Thomas broke his leg against the Cardinals.

The worst case scenario had once again become Thomas’ reality. In what we can all assume was his final game as a member of the Seahawks, Thomas suffered the same fate as his fellow Legion of Boom members — the same fate he had feared for the last two years, driving his entire holdout.

This tragic, yet poetic, ending to Thomas’ career with the Seahawks is an appropriate bookend to what will now be the ultimate cautionary tale for many other NFL players.

The life of an NFL career is a fleeting existence. No matter the stature of the player, it can end in an instant. Any player with the necessary status to command the level of respect needed to orchestrate a holdout will now look at Thomas’ situation before stepping onto an NFL field without proper financial compensation.

Thomas’ broken leg is expected to be completely healed by next year’s free agency, granting him the opportunity to sign with a team he feels will properly value his services this summer without anything in his way.

In the end, this injury likely won’t derail Thomas’ career, but not every player in his shoes will be as fortunate.