Harry Maguire, along with Rob D’Alton, was a crew member aboard the three-person keelboat Akatonbo at the 1964 Tokyo Olympics. The boat was chartered in Japan by skipper Eddie Kelliher, but they encountered several mechanical and other issues with the boat even before they started their first race. As a result, they were classified 20th out of 23 starters, with a best finish of 15th in race four.
| Games | Discipline (Sport) / Event | NOC / Team | Pos | Medal | As | |
|---|---|---|---|---|---|---|
| 1964 Summer Olympics | Sailing | Harry Maguire | ||||
| Three-Person Keelboat, Open (Olympic) | Akatonbo | 20 |