John McEnroe

These days McEnroe, when he is not commentating or involved in one of his many outside interests, is playing on the Seniors Tour, which serves players who no longer compete at the professional level but who still hunger for the competition of their peers. According to London's The Observer, "It is fair to say that without McEnroe, there would be no Seniors Tour." McEnroe is still the player out there who is most passionate about the game; his attitude is the same at 41 as it was at 21.