Izaya with the touchdown - the key word here is athletic. Hunting is also a sport by that definition, but chess, checkers, backgammon, and go are not. They are games - more specifically, board games. Games can have tournaments too, so this isn't a demotion. Basketball may take some of the player's mind, but not nearly as much as chess; sports generally require more physical strength and prowess, and less mental exertion. What mental involvement there is is usually fast-paced and built on trained reactions, not in-depth analysis, since analysis on the level of chess strategy is impractical when under such pressure and physical distraction. If there is analysis and strategy involved, it is generally a bit looser and far more psychological than chess-level strategy, and is usually performed by someone outside of the physical activity (such as a coach).
You wouldn't bring Shaq to a chess tournament, and you wouldn't bring Vladimir Kramnik to the NBA Finals.