(CBS) For years, former Bears teammates Brian Urlacher, Lance Briggs and Israel Idonije told Charles Tillman that he would know when it’s time to retire. After 13 years in the NFL, Tillman’s body was telling him it was time.

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Monday morning came, and Tillman realized there was no turning back. He made the decision official, calling it the end to a 13-year NFL career.

On Wednesday evening, Tillman joined Laurence Holmes on 670 The Score to discuss the decision.

“I just woke up and was like, ‘I think I’m done,” Tillman said. ‘”I think I’m going to retire. Let’s announce it today. All right, cool, let’s do it.’ That was it. I just woke up and was like, ‘Yeah, I’m done, I don’t want to play football anymore.’ And I just retired. It was as simple as that.

“I had an amazing career. I don’t have anything to prove to anybody or myself. I went out on my terms, and I’m super content with that.”

Tillman on Thursday plans to sign a one-day contract with the Bears and will retire with the franchise with which he played 12 of his 13 seasons.

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Now 35, Tillman finishes his career with 38 interceptions and 44 “Peanut Punch” forced fumbles. He will be remembered as one of the greatest players in Bears history.

Tillman will join the FOX NFL Sunday pregame show and will spend time with his young family. When training camp arrives next week, he won’t have any regrets about retirement.

“Nobody misses camp — no, hell no,” Tillman said. “Nobody misses training camp. The thing that I’ll miss the most? My locker room. I’ll miss all the dumb stuff we do in the locker room. The conversations, the games, just the locker room hangout. That’s what I’m going to miss the most about playing in the National Football League, is the locker room.”

Tillman suffered a partially torn ACL late in the 2015 season but attempted to play through it in the Panthers’ fight for the Super Bowl. However, he completely tore the ACL during Week 17 of the season and didn’t play during the playoffs.

Twice during his career, Tillman played for the Super Bowl. He fell shy with the Bears after the 2006 season, then again with the Panthers this past season.

Tillman played the game of football fighting for a Super Bowl. He leaves with no regrets.

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“I fought, I worked, I bled, I sweat, had surgeries,” Tillman said. “I gave everything I had.”