Rafael Nadal and the Price of Greatness

How much do you have to suffer to be a great athlete? Do you have to suffer like Johnny Unitas, the great quarterback of the 1960s, who was unable to lift a fork with his right arm after he retired? Do you have to suffer like Tiger Woods, whose otherworldly drives destroyed his body, resulting in seven back surgeries, five knee surgeries, and two ankle surgeries? Do you have to suffer like Larry Bird, who played basketball with such chronic back and leg pain that when he was taken out of a game to rest, he had to lie on the floor because it hurt too much to sit in a chair?