This is not a book about sports. If you don't know who Frederick Exley is -- and I didn't till I found it among Thomas' books (or was it a recommendation from him...? - well, either way...) -- then don't not read it because you think it's about sports. It has nothing to do with sports, except that that is one of the author's obsessions -- but he could just as well be obsessed about anything else (and he is)... there is very little discussion about sports in it.
Frederick Exley, as his friend Jonathan Yardley said, had one brilliant book in him -- and tore himself apart to get it out of himself. Obsession, mental illness, raw honesty (ultimately), alcoholism... and what a book, it is! It is about one man's search for just a corner of authenticity in an America (of the late 50's, early 60's) that was already becoming wholly inauthentic.
I recently criticised some of these SF writers I've been reading for writing too much, too fast -- All it takes is one book to justify a life -- if it's a real book -- it's that fucking hard to pull either some honesty out of the soul, covered with accretions like Proteus, or to find that little kernel of even objective truth hidden amidst all the sophistry and bullshit. One REAL..., one good book -- and you've paid your debt. In full.
Exley, imo, is paid up.... In full.