Claim: Martina Navratilova is a tennis player.
Evidence: Martina Navratilova -LRB- Martina Navrátilová -LSB- ˈmarcɪna ˈnavraːcɪlovaː -RSB- ; born Martina Šubertová -LSB- ˈmarcɪna ˈʃubɛrtovaː -RSB- ; October 18 , 1956 -RRB- is a Czech and American retired tennis player and coach.