I knew about John Urschel's math prowess from John U. Bacon's book on Big Ten football, "Fourth and Long." You Penn State people can be rightfully proud of him.
The only other pro football player I know of who was an accomplished mathematician was Frank Ryan, quarterback for the Browns in the 1960s. If anyone knows of any others, please post.
When I was a graduate student, I taught a course on Discrete Probability Theory. My best student in that class was an offensive lineman, who eventually played for the pros. Now this course is not for the weak students, as it was a theorem-proof course that started with a chapter on sigma algebra. This man was huge, and he had to bend down to enter the classroom. His test papers were perfect, and what a great pleasure it was to have him for a student. He was not a math major, but I honestly think he could have taught the class on his own. He was empirical evidence that not all football players are stupid jocks. The best part of having him for a student was that he challenged me by asking me some very intelligent questions during my lectures. It was because of him that I developed what I call proof-theorem templates, that I still use in my math classes today.
Once went to a doctor who was graduate of Penn State
Former lineman - huge guy
Told me story of how got into medical school - Paterno
wrote letters and made some phone calls
Went to University of Pennsylvania Med school - one of top schools