Tennis Channel coverage will also be available during the U.S. Open to subscribers of Dish Network, DirecTV and Verizon Communications FiOS TV.Rafael Nadal is among the stars featured in Tennis Channel's U.S. Open ad.The new spot, Air, shows such tennis stars as Roger Federer, Rafael Nadal, Andy Roddick and Venus and Serena Williams in action, but with their images soaring over landmarks in New