Dutch rowing coach Josy Verdonkschot has tested positive for COVID-19 and has gone into a 10-day quarantine in Japan.
This was confirmed by the Netherlands Olympic Committee (NOCNSF) on Sunday.
The news comes after 21-year-old Dutch single sculls competitor Finn Florijn tested positive on Friday.
Another staff member on the Dutch rowing team, as well as Dutch taekwondo competitor Reshmie Oogink and skateboarder Candy Jacobs, tested positive last week.
Some 132 people accredited to the Tokyo Games have tested positive for COVID-19 since July 1, according to organisers.