Tennis Warehouse, which established a European subsidiary in Germany four years ago, has announced a three-year extension of its global online retail partnership with the ATP Tour, taking it through 2014. Tennis Warehouse, which claims to be the world's largest e-commerce platform for tennis products, is a division of Sports Warehouse, a 10-year-old U.S. company that also operates six other online specialty stores: Running Warehouse, Skate Warehouse, Tackle Warehouse, Inline Warehouse, Art's Cyclery and Racquetball Warehouse.