Seattle Seahawks safety Kam Chancellor, one of the NFL’s best at the position, could be calling it a career.

According to NFL Network’s Tom Pelissero, Chancellor is concerned that his health has not improved since suffering a neck injury last season. He discussed his perdicament in a recent social media post.

“I always prayed to God that I would play this game of football until the wheels fall off. Well, the wheels didn’t fall off but God has given me a sign that I just can’t ignore,” Chancellor wrote on Twitter. “…To walk away from the game by choice is one thing, to walk away from the game because of the risk of paralysis is another. My final test showed no healing…Thank you again for all of the support and Love…Time for the next chapter…”

Chancellor has not officially retired, so his $6.2 million and $5.2 million base salaries for 2018 and 2019 are still guaranteed.  Seattle drafted Chancellor out of Virginia Tech in 2010 and he quickly flourished into one of the NFL’s finest safeties. Along with defensive backs Richard Sherman and Earl Thomas, he made up the league’s stingiest secondary, nicknamed the”Legion of Boom.” Chancellor is the team’s last remaining member of the trio, which helped the Seahawks capture the Super Bowl in 2014.