So says the oracle at Delphi, and my thought for the day.  Whether you're an actor or a tennis player, you need to know what kind of player you are.  Are you an ingenue or more of a character actor?  Are you a serve-vollyer or a baseline grinder?  As actors, we all want to think that we can play any role we want - or, as tennis players, that we have an all-court game.  And that's fine to aspire to and train for - but at the end of the day, who you are (and what you're best at) is your strongest asset and will give you the best chance of getting cast or winning that match day in and day out.  Rafael Nadal, in his press conference before this year's U.S. Open final, rolled his eyes as he joked that he would need to employ a serve/volley strategy to beat Novak Djokovic for the title.  He knew that his game was not matching up well against Djokovic of late (having lost five straight championships to the man from Serbia) but the man from Mallorca also knew that playing his game, the way he knew how (and the way he knew he could), was the best chance he would have.  As we know, Nadal wound up losing that match, but fast forward to today - when Nadal clinched for Spain a date with Argentina in the Davis Cup finals - and the world was reminded of the strength of Rafa's personal brand of tennis.  So remember, for every hard court loss, and every time casting decides to go another direction, there will be other venues and projects and opportunities where your style and your skills and your type will be the best - whether that's a red-clay bullring tennis court, a film set with a boom-mic and close-ups on you, or a certain choice of career.  Your best chance for success lies in those opportunities that match who you most naturally are.  As an actor, would I love to play the military action hero in a big-budget motion picture?  Sure; but notwithstanding my real-life U.S. Army background, I would never get cast for that.  Instead, I've carved out a professional niche for myself by playing the soft, quirky romantic.  Would I like to build my tennis game around an explosive 130 mph first-serve?  Okay; but I don't have it.  I have to try to counterpunch.  Point is, both acting and tennis are numbers games; and you play the percentages when you play your own style (and brand) of acting and tennis.  Because this above all:  to thine own self be true and success will be sure to follow.