The term 'Tennis Immortal' is a title given to the greatest players in the sport of tennis. One of these immortals is Arthur Ashe, a four-letter word which is one of the solutions to this crossword. Ashe was an American professional tennis player who won three Grand Slam titles and was the first African American to win the men's singles title at Wimbledon and the US Open. He was also a social activist and humanitarian, and was posthumously awarded the Presidential Medal of Freedom in 1993.