Russia has undertaken systematic doping in swimming for years, the Times newspaper said on Wednesday, as the nation battles a drugs problem that could prevent the country's track and field squad from competing at the Rio de Janeiro Olympics.
              
The English newspaper said its investigation had unearthed "systematic" drug use in the sport, where more than a dozen Russian swimmers were suspended in the past three years for doping.
              
The Times said Dr Sergei Portugalov, Chief of the Russian Athletics Federation's Medical Commission, who was said to have provided banned substances to Russian athletes, was also involved in swimming.
              
Dr Portugalov was named in a World Anti-Doping Agency (WADA) report on systematic doping in Russian athletics a few months ago.
              
"Calls for Russian swimmers to be excluded from the Games will grow after the investigation revealed that Portugalov, the doctor recommended for a lifetime ban by WADA as a key player at the heart of Russia's doping scandal, actively encouraged the national swimming team to adopt a systematic doping policy," the newspaper said.
              
"Since 2009, when Portugalov first offered to 'assist' Russian swimming, 23 swimmers have been handed suspensions for doping and the tally for all aquatics sports exceeds 40 in the past decade."
              
Russian Swimming Federation President Vladimir Salnikov, a quadruple Olympic gold medallist, and the authority's spokeswoman Margarita Balakireva were not immediately available for comment.
              
The report comes only a day after Russia's wrestling federation said there were "tens" of positive tests among its athletes would could miss out on the Olympics.
              
Russian sport was thrown into turmoil last year when a report by WADA exposed endemic cheating and corruption in Russian athletics.
              
Russian track and field athletes have been suspended from international competition and will miss the Olympics if the country cannot get the ban overturned, a humiliating blow to the pride and prestige of a sporting superpower.