I feel like pro athletes aren't the tossup/Republican constituency that people here are saying they are.
The racial breakdown of the Big 4 sports leagues are (first 3 from
this link, NHL from the title of
this article, and finding out manually that about 30 of those 43 are black:
MLB (750 players) - 58% white, 32% Latino, 8% black
NBA (390 players) - 74% black, 21% other (multiracial I guess)/white
NFL (1696 players) - 70% black, 27% white
NHL (713 players) - 94% white, 4% black, 2% other
This means that only ~46% of Big Four athletes are non-Hispanic whites, and this is likely even lower among American citizen athletes given that the 94% white NHL is only ~27% American, and many NBA white players are Europeans. Not to mention the nearly entirely American NFL being 70% black.
Yeah, I think it's fair to say Biden will likely be carrying pro athletes (albeit they are an incredibly small and likely low turnout group).