Jack Kramer

John Albert Kramer was an American tennis player of the 1940s and 1950s, and a pioneer promoter who helped drive the sport towards professionalism at the elite level. Kramer also ushered in the serve-and-volley era in tennis, a playing style with which he won three Grand Slam tournaments. He also led the U.S. Davis Cup tennis team to victory in the 1946 and 1947 Davis Cup finals.