In addition, out-of-state or out-of-country athletes are subject to local taxes for their work.
Example:
Mickey Mantle plays for the NY Yankees and lives in NYC.
He plays 30 games in California (against the Angels, Padres, Giants, Athletics) during the course of the year.
California expects to be paid 30/162 (30 games of the 162 game season) in state income tax based on his salary, because his income was partially earned in that State. And so on.
Athletic teams have bunches of accountants doing this sort of work every year.