The update has brought the total number of those infected since July 1 to 81, with the cases detected among athletes residing in the Olympic village, members of foreign delegations and personnel.
Additionally, the novel coronavirus has been detected in four athletes and accompanying personnel from training camps located outside Tokyo, the organizers added.
While the athlete who tested positive for COVID-19 was not from Japan, the individual's country of origin was not specified in the announcement. Also, tests of a staff member of one of the teams that arrived in Japan and eight contractors working at the Olympics gave positive results.
Overall, more than 30 of these new infection cases are foreign nationals.
The Summer Olympics in Tokyo was originally set for 2020 but were postponed in the spring of last year due to the coronavirus pandemic. The Games are set to take place from July 23 to August 8 this year.