Larisa Simonova/Petr Triandafilidi (Vladivostock, RUS) qualified for the 2021 Russian Mixed Doubles B-Division Championship playoffs, dropping their quarterfinals match 9-3 against Aleksandra Stoyarosova/Ivan Kazachkov (Novosibirsk, RUS). of the 2021 Russian Mixed Doubles B-Division Championship in Sochi, Russia;
 
Simonova/Triandafilidi finished 4-1 in the 0-team qualifying round. . In their opening game, Simonova/Triandafilidi lost 12-4 to Maria Drozdova/Danil Kiba (St. Petersburg, RUS), then responded with a 9-3 win over Alevtina Muravieva/Andrey Suvorov (Moscow, RUS). Simonova/Triandafilidi won 8-5 against Anna Samoilik/Danil Dmitriev (Krasnoyarsk, RUS), then won 12-9 against Nadezhda Kulikova/Artem Kulikov (Moscow, RUS) and 6-4 against Maria Tsebriy/Maksim Shibilkin (Moscow, RUS) in their final qualifying round match.
 
Simonova/Triandafilidi ranks th overall on the Year-to-Date rankings with points earned so far this season.