The ROC's two Svetlanas, Kolesnichenko and Romashina, posted the top score in the technical routine Tuesday in the artistic swimming duet competition, just as they did in the free routine preliminary.
China's Huang Xuechen and Sun Wenyan finished second in each phase of the competition.
The USA's Anita Alvarez and Lindi Schroeder just missed qualification for the final day, placing 13th.
The top 12 advanced to the last day of competition in the duet event, in which they will perform a free routine that will replace the score from their preliminary round. The technical score carries over.