At least 85 athletes from the 387-strong Russian Olympic team announced last week have so far been barred from the Rio Games in connection with the country's doping scandal.
International federations in canoeing and modern pentathlon ruled out seven on Tuesday, including an Olympic gold medalist, following earlier rulings in swimming and rowing. Some appeals are likely.
Russian President Vladimir Putin's spokesman Dmitry Peskov told Russian media that Putin had discussed the doping issue with his national security council.
"The topic of the recent International Olympic Committee ruling relating to Russian athletes was raised ahead of Putin's planned meeting tomorrow with the Russian Olympic team," Peskov was quoted as saying.
The vast majority of the Russian athletes who miss out are in track and field, where 67 athletes were ruled out when a ban on the Russian team was upheld at the Court of Arbitration for Sport last week.
More are falling foul of new rules imposed in the wake of the country's doping scandal.
While Russia avoided a blanket ban from the International Olympic Committee, it has lost several medal contenders to new IOC rules imposed Sunday banning Russia from entering athletes who previously doped.
Alexander Dyachenko, an Olympic champion in 2012, was among five canoeists ruled out after being named in a recent report by World Anti-Doping Agency investigator Richard McLaren alleging a state-sponsored doping cover-up.
McLaren's report last week specifically detailed how Russian state officials allegedly intervened to cover up hundreds of failed drug tests.
Dyachenko won gold in the men's double kayak 200 meters at the 2012 London Games.
"The ICF will continue its strong zero-tolerance stance and remove all athletes that contravene its rules in anyway," said Simon Toulson, the International Canoe Federation's general secretary. "If you step out of line you won't make the start line."
The four other banned canoeists are Alexei Korovashkov - a 2012 bronze medalist in the C2 1,000 meters event - Andrei Kraitor, Elena Anyushina and Nataliya Podolskaya.
The ICF also said that Russia would not be allowed to enter boats in four events in which the excluded athletes would have raced. Therefore, Austria, Germany, Sweden and Iran are in line to receive their places.
Meanwhile, the International Modern Pentathlon Union named the two Russians it had suspended as Maxim Kustov and Ilya Frolov, saying they both featured in the McLaren report. Kustov's place in the men's event passes to a Latvian athlete, while Frolov had only been entered for Rio as a reserve.
Three Russian rowers have also been excluded. Ivan Podshivalov and Anastasia Karabelshchikova were excluded because they previously served doping bans, while Ivan Balandin from Russia's men's eight was implicated in the McLaren report, World Rowing said.
Meanwhile, volleyball player Alexander Markin told local media he had been dropped due to a positive test earlier this year for the banned substance meldonium, even though he had not been banned. The international volleyball federation did not immediately respond to a request for comment.
The head of the Russian Wrestling Federation told the R-Sport agency that two-time world champion Viktor Lebedev was ineligible because he was given a doping ban in 2006.
On Monday, swimming's world governing body FINA ruled out seven Russians including reigning world 100m breaststroke champion Yulia Efimova.
Legal challenges are looming.
Efimova's agent has said he is preparing an appeal to the Court of Arbitration for Sport, and the Russian Canoe Federation's general secretary Irina Sirayeva said that the five banned could follow suit.
"The intention to defend the athletes is there," she told R-Sport.
Triple jumper Ekaterina Koneva - a former world championship silver medalist - told local media she was considering a lawsuit in civil court.
There was good news for Russia as its team of 18 shooters received approval to compete from the sport's international federation. Also, Russia also looks set to field a full team of four players in Olympic badminton, the Russian Badminton Federation said Tuesday, citing assurances from the Badminton World Federation.
Previously, archery and equestrian sport's world governing bodies said they had no objection to the Russians entered in their sports.
Lists of Russian athletes approved by international federations must still be approved by CAS arbiters who can reject athletes not tested outside Russia.
The IOC refused to accept testing done by Russian agencies because of evidence that the process was corrupted.