Swimming's governing body, FINA, has ruled seven Russian swimmers ineligible to compete at the Olympics, including three it says were linked to recent allegations of a major doping cover-up by Russian authorities.
Reigning world 100-meter breaststroke champion Yulia Efimova is among four Russian swimmers who FINA says were withdrawn by the Russian Swimming Federation because they previously served doping bans.
The International Olympic Committee on Sunday restricted athletes with previous doping bans from representing Russia.
FINA says three more swimmers were identified by World Anti-Doping Agency investigator Richard McLaren when he examined evidence that Russian government officials ordered the cover-up of hundreds of doping tests.
They are 2008 Olympic silver and 2012 bronze medalist Nikita Lobintsev, bronze medalist Vladimir Morozov and world junior record holder Daria Ustinova.