orig. John Albert Kramer born Aug. 1, 1921, Las Vegas, Nev., U.S. U.S. tennis player and promoter. He won the Wimbledon singles (1947) and men's doubles (1946-47), the U.S. singles (1946-47), men's doubles (1940-41, 1943, 1947), and mixed doubles (1941) and was on the winning Davis Cup team in 1946. He played professional tennis from 1947 to 1952 and was instrumental in promoting open tennis, in which amateurs competed with professionals in major tournaments. He helped establish the Association of Tennis Professionals