Maria Sharapova's cover shoot for the cover of Esquire in Bulgaria, Rafael Nadal practices in Madrid, Patrick Mouratoglou talks about national systems and more

The Daily Bagel is your dose of the interesting reporting, writing and quipping from around the Internet.

• Maria Sharapova is on the cover of Esquire in Bulgaria.

• Jeff Sackman at Heavy Topspin takes a look Kei Nishikori's Open Era-best 75-20 record in deciding sets.

• Based on this photo from Madrid, is Rafael Nadal switching back to his old Babolat racket?

• Interesting thoughts from Patrick Mouratoglou on how national systems can limit the ability produce champions:

The first one is the system and each country defines its own one with a way to train players insisting on parameters that are different in each system. For example, the Spanish system insists on hitting many balls on clay, with a lot of physical training for many hours. This helps developing a type of game that you need to be super fit and a big fighter to become a top player.



The second is the culture—if the country also promotes a certain kind of behavior. For example, the French mentality gives a lot of credit to people who are gifted rather than promoting winners or fighters. That is one of the reasons why French tennis is full of talented but non-winner players.



The third is the influence of the national champions. It is always easier for kids to identify themselves with the best player of their country. That is the reason why they are influenced by the type of best player of their country. If the Czech champions hit flat, the kids will be keen on adopting the same style of play.

• The Americans have descended on Europe:

[tweet=https://twitter.com/Riske4rewards/status/593823371391070208]