Not being able to read until he was in middle school didn’t stop Mark Schlereth from becoming a successful NFL player.

As a seventh grader, Schlereth was called on to read out loud in front of the class, but was unable to make out any words on the page. He worked extensively with his English teacher, and by the end of the year, he was able to read.

"As far as self-esteem was concerned, I had absolutely none when I came to school," Schlereth said. "When you don't learn to read until you're in the 7th grade, you hide a lot of things. What it ended up doing for me was it made me have to learn through different avenues, by listening, by watching people, by developing common sense.

"It also helped mold me into a great athlete because I'd pick out those kids who made fun of me in class and then we'd go play dodge ball or football and I wanted to prove something to those kids. I wasn't mean or hostile. I've never been in trouble. I've never been an aggressive child. But I wanted to prove to them that I did have self worth and that came from my ability as an athlete."

Schlereth did have exceptional athletic ability. He went on to play 12 years in the NFL and won three Super Bowls. His perseverance helped him overcome his dyslexia and his struggles to make the NFL.

To read more of his story, visit the Chicago Tribune.