Rashean Mathis, 35, played for Jaguars and Lions during career

Why Rashean Mathis retired (1:54)

Rashean Mathis played corner for the Lions and Jaguars and served as a mentor in both locker rooms. ESPN Lions reporter Michael Rothstein says Mathis has studied CTE and understood it was time to walk away from football. (1:54)

Veteran NFL cornerback Rashean Mathis announced his retirement Tuesday after 13 seasons in the NFL.

The 35-year-old Mathis was drafted in the second round by the Jacksonville Jaguars in 2003 out of Bethune-Cookman and started in the secondary for 10 seasons with the Jaguars. He was released by the Jaguars following the 2012 season and signed with the Detroit Lions during training camp in 2013.

For the past three seasons, he's been a valuable member of the Lions both on the field and off of it, mentoring Detroit's young secondary led by Darius Slay.

Mathis played in 175 games in his career, making 636 tackles with 32 interceptions, eight forced fumbles, five fumble recoveries and one sack.

After the season ended, Mathis said he would think about whether he would play one more season. Mathis was entering the second year of a two-year deal in 2016 but he wanted to weigh his options before making a decision.

Mathis suffered a concussion in Week 7 against Minnesota, had symptoms show up almost a week later and ended up on injured reserve, ending his season. After the season ended, Mathis said the concussion would not play a role in whether he returned to the game.

"I'm healthy with no effects, so I always put things in perspective and I look at it as: If I had a concussion in Year 5 and I went through this, would I play Year 6 knowing what I know now?" Mathis said in January. "And that would be a 'Yes, I would.' So that means I have to be in that same mindframe, meaning that if I decided to play, the concussion wouldn't play a factor in it."

Mathis also told ESPN in January that if he was going to retire, he would like to do it with a one-day contract with the Jaguars in his hometown of Jacksonville. The Jags drafted him, and he spent the majority of his career with the team.

It is not clear if that is still his plan. Mathis did not return a message seeking comment Tuesday.

"Jacksonville is home, so I think it would be a slap in the face if I did anything other than that," Mathis said. "I respect my 10 years there and hopefully the people of Jacksonville respect me as well. But Jacksonville was always fun. It was never any bad blood, really, there.

"It's 10 years there. Ten years weighs a lot."