John Urschel quit the NFL for a career in math. It wasn't just
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PFW Preview Guide 2016 by Shaw Media - Issuu
Genius John Urschel Explains His Decision To Retire From NFL
Ravens OL John Urschel, 26, abruptly retires days after findings
John Urschel retires from the NFL at age 26
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Genius John Urschel Explains His Decision To Retire From NFL
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