Martina Navratilová; born October 18, 1956, in Prague, Czechoslovakia) is a former World No. 1 women\s tennis player. Billie Jean King said about Navratilová in 2006, \"She\s the greatest singles, doubles and mixed doubles player who\s ever lived.\" Tennis writer Steve Flink, in his book The Greatest Tennis Matches of the Twentieth Century, named her as the second best female player of the 20th century, directly behind Steffi Graf. Tennis magazine has selected her as the greatest female tennis player for the years 1965 through 2005. Tennis historian and journalist Bud Collins has called Navratilová, \"Arguably, the greatest player of all time.\" Navratilová won 18 Grand Slam singles titles, 31 Grand Slam women\s doubles titles (an all-time record), and 10 Grand Slam mixed doubles titles. She reached the Wimbledon singles final 12 times, including 9 consecutive years
Who is the greatest grass court player?