In the 1920s and 1930s, psychology was beginning to be taught at coaching schools. Some coaches used what they were learning about sports psychology while coaching their teams. Paul Brown was head coach of the Cincinnati Bengals. He began using psychological testing with his players. His tests eventually became known as the beginning of the National Football League’s tests that are still used today. During the 1940s, psychology was starting to be used as a way for athletes to improve their performance. Psychology professor Dorothy Hazeltine Yates helped a boxer try to improve his skills through psychology; the boxer then went on to have the best fights of his career. Also during the 1940s, hypnosis was starting to be used to help athletes to relax. During the 1950s, David F. Tracy began using psychological methods to help players on the St. Louis Browns, a major league baseball team, now known as the Baltimore Orioles.