Why an NFL player who retired to pursue a PhD at MIT chose to live on $25,000 a year

John Urschel had a short but lucrative, NFL career. The offensive lineman, who retired at age 26 in 2017 to pursue his PhD at MIT, earned $1.8 million over his three seasons with the Baltimore Ravens.

His salary was as high as $600,000 in 2016, but Urschel never lived like he was making six figures. In fact, he did the opposite.

"I drive a used hatchback Nissan Versa and live on less than $25,000 a year," the athlete wrote on The Players' Tribune in 2015.

My Nissan Versa in the Ravens parking lot.

A post shared by John Urschel (@john_urschel) on

Urschel bought the Nissan after he was drafted by the Ravens in 2014. It cost him $9,000, just a fraction of his $144,560 signing bonus.

Even his mom has joked about the Versa, which had 30,000 miles on it when Urschel bought it:

My mom's got jokes...

A post shared by John Urschel (@john_urschel) on

It's his "dream car," he told ESPN in 2015. "It's great on gas. It's surprisingly spacious. And you know what the best feeling is? You're driving into a parking deck, it's near full and you're on the first level and there is that space that everyone has passed because they said, 'No, we can't park in there.' And I take my Versa and I just go right in there."

He didn't live on a modest $25,000 a year and drive a used car "because I'm frugal or trying to save for some big purchase," Urschel noted. "It's because the things I love the most in this world (reading math, doing research, playing chess) are very, very inexpensive."

Former NFL player John Urschel
Matt Hazlett | Getty Images
Former NFL player John Urschel

Urschel not only loves math, he's quite good at it. He earned a bachelor's and master's in mathematics while maintaining a 4.0 GPA and his work has been published in numerous journals, including the Journal of Computation Mathematics and the SIAM Journal of Numerical Analysis.

"The things I love the most in this world (reading math, doing research, playing chess) are very, very inexpensive." -John Urschel, former NFL player and current PhD student

Currently, he's pursuing his doctorate at MIT.

Urschel's new salary might look different than his NFL salary, but "I have the means to make a good living and provide for my family, without playing football," he wrote on The Players' Tribune. "I have no desire to try to accumulate $10 million in the bank; I already have more money in my bank account than I know what to do with."

Like this story? Like CNBC Make It on Facebook!

Don't miss: NFL player who lives on $60,000 a year says this book changed his mindset about money