Despite an 11-year career that included Pro Bowl and Super Bowl appearances, former Chicago Bears defensive end Adewale Ogunleye says that one of his biggest takeaways from his time in the league was learning the value of a dollar.

Though he had been projected as a first or second round pick after a strong college career, Ogunleye ended up entering the NFL as an undrafted free agent due to injuries sustained during his senior season.

This meant he didn't receive nearly as high a salary as the top draft picks that year. His $200,000 rookie salary paled in comparison to the $6 million earned by No. 1 pick Drew Bledsoe. But Ogunleye says that in a way, his financial situation was a blessing.

"I knew I couldn't live off of $200,000 for the rest of my life [if I got hurt]," he tells CNBC Make It of his rookie salary. "So I came into the league with that mentality that I've got to keep working and that if it didn't work out, I had to get another job."

While he did eventually secure a $33 million contract from the Chicago Bears in 2006 and finished his career with nearly $36 million in earnings, Ogunleye says the need to grind for a major NFL contract instead of having one right off the bat helped him avoid uncomfortable situations with regards to people in his life asking for money.

"I think where I had a little bit of an advantage [over the drafted players] was I didn't have the money," Ogunleye, who grew up in the Park Hill Projects in Staten Island, says. "All the handouts, all the people who wanted to put their hands in my pockets, I told them I didn't have that kind of money."

Over the years, he still enjoyed the trappings that came along with being a high-paid athlete. But by the end of his career, Ogunleye's material appetites had changed.

"My first year in the league I'm 21, 22 years old. I come into the locker room and I see Lamborghinis and Ferraris and I'm like 'Wow, this is it!'" he says. "By year 10, I could care less. I just need a car to get me from point A to point B."

He says that as he got older, he began to appreciate how short an athlete's career is when taken in the context of their life.

"As you get older and more mature and those things start to seep in, they also seep into how you manage your money," he says. "At the end of the day, this is a short period of time you have. Tom Brady has played 20 years in the NFL, but he's still going to have to find something to do with his time and energy when he's done. He is still a young man."

Now 44, Ogunleye is the head of the athletes and entertainers segment at the global financial services firm UBS. He talks to young men and women who are, in many cases, coming into massive sums of money about how they can void the pitfalls and mistakes that he saw doom teammates in the NFL.

"I made mistakes, and by the grace of god my mistakes were not catastrophic," he says. "I knew nothing about finances. The fact that I didn't lose everything was luck."

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