It seems like you can play tennis on any kind of surface and any place as long as there is a tennis court. Downtown Manhattan, on the top of a skyline, inside a swimming pool...
Now, add a bay. Rafael Nadal and Roger Federer played in exhibition for Doha this past Sunday in the water.
Visit the link below to view the video: http://www.hulu.com/watch/204110/nbc-today-show-tennis-stars-play-on-floating-court