BEIJING, Feb 15 — Teenage Russian figure skater Kamila Valieva starts her bid for a second gold medal on Tuesday at the Beijing Olympics, as anger mounts over the decision to allow her to compete despite failing a drugs test.

The 15-year-old is at the centre of a raging controversy after the Court of Arbitration for Sport ruled on Monday that she could carry on at the Games even though she tested positive in December for the banned substance trimetazidine, which boosts endurance.

It also put the spotlight once more on doping by Russian athletes, who are not allowed to take part at the Games under their flag because of a state-sponsored doping programme that reached its peak at its home 2014 Sochi Olympics.

The CAS ruling was celebrated in Russia but provoked fury elsewhere, with the United States Anti-Doping Agency (USADA) accusing the country of "hijacking” the Beijing Olympics.

Valieva, who has not been cleared of doping and could still face punishment at a later date, told Russian television: "These last few days have been very difficult for me.

"I am happy but at the same time tired emotionally.”

Starting to cry, she added: "These are tears of happiness, but also it seems sadness.”

Valieva is favourite to win gold in the women’s singles skating, which starts on Tuesday, but the International Olympic Committee says there will be no medal ceremony in Beijing if she comes in the top three — unprecedented in the history of the Games.

Valieva led Russia to team gold last week, before a Stockholm laboratory reported that she had failed a drugs test from December 25, but the medal ceremony for that competition will also not take place.

In ruling that Valieva should not be suspended, CAS said that there were "exceptional circumstances”, including her age and the fact it had taken six weeks for her failed test to be reported.

Matthieu Reeb, CAS director general, said Monday preventing Valieva from competing would have caused her "irreparable harm”.

Denis Oswald, a senior IOC official who oversaw an investigation into widespread Russian doping in Sochi, said that Valieva’s case was different. 

"The state doping was a big system and it doesn’t seem to be such a situation here,” he told a press conference on Tuesday, adding they will look into the coaches and others surrounding the teenager.

"Of course you can imagine a girl of 15 does not do something wrong alone,” he said.

"The entourage will be investigated.”

In the United States, USADA expressed sympathy for Valieva but chief executive Travis Tygart said that "for the sixth consecutive Olympic Games, Russia has hijacked the competition and stolen the moment from clean athletes and the public”.

US sprinter Sha’Carri Richardson, who was barred from competing at last summer’s Tokyo Olympics after testing positive for marijuana before those Games, angrily contrasted her treatment with Valieva’s.

Valieva will go in the short programme of the figure skating on Tuesday but gold will not be decided until after the free skate on Thursday.

Gu settles for silver

Nine gold medals were up for grabs in the Chinese capital on Tuesday.

World champion Corinne Suter confirmed Switzerland’s alpine skiing dominance at the Games when she streaked to victory in the women’s downhill for the country’s fourth gold.

Two-time skiing gold medallist Mikaela Shiffrin, who is yet to win a medal in Beijing, came 18th.

There was another Swiss winner earlier in the day in the form of Mathilde Gremaud in women’s freestyle slopestyle.

Gremaud triumphed ahead of Californian-born Chinese sensation Eileen Gu, the face of the Games and gold-medal winner last week. Gu, 18, had to settle for silver.

"I wanted to get on the podium more than anything, so landing I just felt relieved,” said Gu, who was third after her first run and took a hefty backwards tumble on her second, leaving her sweating for a medal going into her third and final go.

"I’m out here representing myself and the sport to people so just to be able to put down a run and show people what’s possible when you’re under pressure is another thing that I’m proud to represent.”

Gu will have another shot at a medal in freeski halfpipe, with the qualification round taking place on Thursday and the final on Friday.

Austria’s Anna Gasser won a dramatic snowboard Big Air gold to retain her title. — AFP