The ATP website has a great resource called the "ATP Performance Zone", where various stats are presented from the game's greatest players. Included are broad stats like career winning percentage, and more specific records such as winning percentage after losing the first set. After playing around with some of the options, it is really amazing how the top players are separated from everyone else.  For instance, take the stat winning percentage "After Losing First Set". What would you guess the top players' winning percentage is after losing the first set? You may be surprised to learn it is below 50%, with Rod Laver owning the best at 49%. For current ATP players, Nadal is at the top of the list with 43%, followed by Djokovic at 41%. What about other top 10 players? Berdych (26%), Ferrer (31%), Raonic (28%), Murray (40%), Federer (40%), Wawrinka (33%), Nishikori (35%), and Tsonga (34%).  Now look at other players in the top 30:

15th ranked player, Gael Monfils (26%)

20th ranked player, Benoit Paire (23%)

25th ranked player, Phillip Kohlschreiber (18%)

30th ranked player, Ivo Karlovic (23%)  

There is a clear distinction between the top 10 and everyone else in this statistical category. Not surprising, the players who have dominated the game for the past decade (Federer, Nadal, Djokovic, & Murray) are all at or above the 40% mark. 

Let's take a look at another stat category, winning percentage for the "Deciding Set".  Looking at the top 10 again: Djokovic (74%), Federer (64%), Murray (69%), Nadal (69%), Ferrer (65%), Nishikori (78%), Tsonga (63%), Wawrinka (58%), Raonic (61%), and Berdych (57%). Now look at other players in the top 30:

15th ranked player, Gael Monfils (57%)

20th ranked player, Benoit Paire (54%)

25th ranked player, Phillip Kohlschreiber (54%)

30th ranked player, Ivo Karlovic (51%)  

Take what you will from these numbers, but consider the reasons why the top players are leading these lists.  Simply put, the top players keep fighting when others give up; the top players keep believing in themselves when others begin to doubt; the top players raise their level when the match is on the line whereas other players fade down the stretch.  It all boils down to mental toughness.  The top players are the most mentally fit and they use this mental strength to separate themselves from everyone else.  

So how can you use this data to improve your game?  Think about your own playing history. How well do you do after losing the first set?  How well do you do in the deciding third set? Consider the reasons why you may struggle in one or both of these areas.  Do you fade in the third set due to your fitness level?  Do you get negative or stop believing when you lose the first set?  Do your nerves interfere with your performance during the big moments in the match?  These are all questions to consider when trying to figure out where you can improve your game.  Reflection leads to awareness; awareness leads to problem solving; problem solving leads to action; action leads to improvement.