Rafael Nadal is the latest sports star to be targeted by a Russian hacking group that claims to be releasing official data from the World Anti-Doping Agency (WADA).

Fancy Bears, which is said to have links to the Russian government, had already published a series of medical records that stated when Olympic athletes had sought a therapeutic use exemption (TUE) to use substances banned by WADA for verified medical reasons.

Australian rower Kim Brennan, who won a gold medal at last month’s Olympic Games and was flag-bearer at the closing ceremony, was one of the athletes previously named.

On Monday, the group published further files relating to 26 athletes, including Nadal, four-time Olympic gold medallist Mo Farah and golfing star Justin Rose.

The fact Nadal was included is sure to have raised eyebrows across the tennis world.

The Spaniard, who has won 14 grand slam titles and won tennis gold medals at the 2008 and 2016 Olympic Games, initiated legal action against former French politician Roselyne Bachelot in April after she accused him of doping.

Nadal was – according to the leak – given TUEs in 2009 and 2012.

On both occasions, the exemption was for the use of betamethasone, a steroid medication that helps prevents inflammation.

Nadal did not play from June 2012 to February 2013 due to injury.

Farah was twice given TUEs, said Fancy Bears, in 2008 and in 2014.

English golfer Rose, who won the 2013 US Open, needed an exemption for the anti-inflammatory drug prednisolone earlier this year, the leak added.

Nadal in action at the Rio Olympics. Photo: Getty

Other athletes targeted in the leaks so far have been tennis sisters Serena and Venus Williams, gymnastics star Simone Biles and cyclists Chris Froome and Bradley Wiggins.

There is no suggestion that the athletes named in the leaks have done anything untoward – after all, the list surrounds exemptions given by WADA.

But on their website, Fancy Bears said: “We are going to tell you how Olympic medals are won. We hacked World Anti-Doping Agency databases and we were shocked with what we saw.

“Wait for sensational proof of famous athletes taking doping substances any time soon.

“We stand for fair play and clean sport.”

The WADA response

Further leaks are expected and WADA’s director general Olivier Niggli said last week: “WADA deeply regrets this situation and is very conscious of the threat that it represents to athletes whose confidential information has been divulged through this criminal act.

“WADA condemns these ongoing cyber-attacks that are being carried out in an attempt to undermine WADA and the global anti-doping system.”

Vladimir Putin is not happy. Photo: Getty

Russian President Vladimir Putin says the many athletes seeking TUEs means the decision to ban his country’s athletes from the Paralympic Games, on suspicion, was “hypocritical”.

“We don’t approve of the hackers’ action [but] it has helped reveal that people, who took part in the Olympics and looked absolutely healthy, had taken banned medicines giving them an edge in competition,” he said.

The Nadal/Bachelot back story

Ms Bachelot is being sued after saying on French TV in the fallout to Maria Sharapova’s positive drugs test: “We know that Nadal’s famous seven-month injury [in 2012] was because he tested positive.

“If a player takes a significant time out from the sport, it’s because he tested positive and the whole thing was covered up.”

Nadal said in response that he was “gonna sue her” because he was “tired” of having to defend himself against similar remarks.

Ms Bachelot used this defence when asked to clarify her comments: “Newspapers such as Le Monde and L’Equipe, and managers like Yannick Noah have accused him of doping.”

Ex-tennis players Christopher Rochus and Daniel Kollerer have also accused Nadal of taking performance-enhancing drugs.

Nadal, who said it was time “insulting or false allegations” against athletes stopped, will donate any compensation that he wins to charity.