| ANDYMURRAY | Only tennis player to have won two Olympic singles titles |
| RODLAVER | Only tennis player to have won two calendar-year singles Grand Slams in 1962 and 1969 (3,5) |
| ANDY | With 41-Down, first tennis player to win two Olympic singles gold medals |
| LINUSCARLPAULING | US chemist who became the only person to have won two unshared Nobel Prizes (5,4,7) |
| SANGER | Frederick -; considered the "father of genomics", the only person to have won two Nobel Prizes in chemistry (6) |
| STEFFIGRAF | The only tennis player to have won each of the four Grand Slam singles titles at least four times |
| GRAF | Who is the only tennis player to have won all four majors and Olympic gold in the same year? (4-) |
| GRANDSLAM | Rod Laver is the only tennis player to have twice won this title (5,4) |
| GORANIVANISEVIC | The only tennis player to win the men's singles title at Wimbledon as a wildcard |
| GRIGORDIMITROV | The only male Bulgarian tennis player to have been ranked in the ATP singles top ten |
| PELE | Who is the only player to have won the World Cup three times? (4) |
| MESSI | Players to have won the FIFA Men's Player of the Year since 2008: Lewandowski, Modric, Ronaldo, and... (5) |
| CURIE | One of the four people who have won two Nobel Prizes |
| EDDIECHARLTON | Which Australian professional billiards player is the only player to have been world championship ru |
| STAUB | Only MLB player to have 500 hits with four different teams |
| KEEGAN | Who is the only British player to have been voted European Footballer of the Year twice? (6) |
| KAPILDEV | Indian cricketer, the only player to have taken more than 400 wickets and scored 5000 runs in Tests (5,3) |
| KERR | Who is the only player to have taken a five-wkt haul in the recently-concluded WPL 2025? (6,4) |
| AMELIA | Who is the only player to have taken a five-wkt haul in the recently-concluded WPL 2025? (6,4) |
| HAMM | Mia ____ won two Olympic gold medals and two World Cups with the US women's national soccer team |
