The International Swimming Federation's (FINA) Artistic Swimming Olympic Games Qualifying Tournament (ASOGQT), offering 13 Olympic berths across two disciplines, is due to begin in Barcelona tomorrow.
Team technical routines are scheduled to launch the event tomorrow, followed by team free routines on Friday (June 11).
Three team places at Tokyo 2020 are due to be decided at the ASOGQT.
Hosts Spain, Hungary, South Korea, France, the United States, Italy and Greece are the nations vying for the final three Olympic berths.
Egypt, Canada, Australia, China, Ukraine, Olympic hosts Japan and an ROC side have already booked their places at Tokyo 2020.
The ASOGQT will also offer eight Olympic berths to duets, with the weekend reserved for pairs action.
FINA lists 25 duets as having entered this competition, with representatives from Egypt, Canada, Japan, ROC, Australia, China, Ukraine, South Africa, Mexico, Kazakhstan and Spain having already booked their place at Tokyo 2020.
Tokyo had been due to host this artistic swimming qualifier, but complications brought about by the coronavirus pandemic led to it being moved to Barcelona and the Piscina Sant Jordi.
Tokyo 2020-qualified swimmers will be in action in Catalonia too, as the finale of the FINA Artistic Swimming World Series is to be run in parallel to the ASOGQT.
Artistic Swimming World Series legs were held in Budapest and Kazan this season, while Canada and the US also staged online competitions.