http://online.wsj.com/article/SB100...92.html?mod=WSJ_hp_MIDDLENexttoWhatsNewsFifth Perrota asks why Serbia, with 3500 tennis players and about 440 courts, has better tennis players than the US, with 165000 juniors. I think the real answer is Ivanisevic. His career lasted from 89-2001, which would have been the youth of Djokovic et al. He was Croatian but it was all one country at the time. Same with Borg and then the next generation of Swedes.