There's almost zero chance these things are published as the player writes them, and in some cases I suspect the player never even writes a first draft at all. There's an old approach to autobiographical works in which the "author" simply is interviewed by and/or provides various recollections to the writer/editor, who then condenses it all into something cohesive, trying to maintain the subject's word choices and personality as much as possible. Or, the writer uses a combination of written and oral information to do the same thing.
Sometimes the actual writer gets an "as told to" credit; other times it's just a straight ghostwriting deal.
As Rome said, on the whole, these Players Tribune things – even when they are trying to sound casual and conversational – are way too "writerly" to be written by people who don't write for a living.