Tennis is a truly international sport, but it often becomes a very nationalistic game these days. Many of the powerhouse tennis countries such as Spain, France, Russia, United States, Czech Republic, etc. have so many players competing that there are often intra-country rivalries played out on the Grand Slam stages amongst players of similar ages, who have competed against one another for years. For example, at the 2007 Australian Open, Americans James Blake and Robby Ginepri have played and Mardy Fish and Andy Roddick will clash in the quarters, while Frenchmen Gael Monfils and Richard Gasquet played a thrilling match and Czech countrywomen Lucie Safarova and Nicole Vaidisova will compete in the quarters. They all know each other's games very well and they often have additional pressures based on past history and relationships... all adding a little extra intrigue to the matches!