I submit that tennis is the most beautiful sport there is, and also the most demanding....Basketball comes close, but it's a team sport and lacks tennis's primal mano a mano intensity. Boxing might come close- at least at the lighter weight divisions- but the actual physical damage the fighters inflict on each other makes it too concretely brutal to be really beautiful- a level of abstraction and formality (i.e., play) is necessary for a sport to possess true metaphysical beauty (in my opinion).