I think John McEnroe was the greatest tennis player I've seen play the game. When he was at his best he was simply superb, that touch, noone nowadays comes anywhere near what he could do with a racket and ball. I would see him come to the net and have a ball hit at him full on with enormous power and he would delicately touch the ball over the net, sometimes just dropping it over or placing it with no spin or pace at an incredible angle. I've never seen anyone do that ever either before or after. As for his temper, well he simply got better as he got angry but its not why I thought him such a great player. The other aspect was his never say die attitude, he simply never gave up and played for all he was worth.