An overwhelmed Kamila Valieva finished fourth in the women's figure skating at the Beijing Olympics on Thursday as a doping scandal engulfing the pre-Games favorite appeared to take its toll.

Her Russian teammate Anna Shcherbakova took gold after the 15-year-old Valieva produced an error-filled performance and was left distraught at the end of her free program.

Another Russian, Alexandra Trusova, took silver, and Japan's Kaori Sakamoto won bronze.

"The importance of this is so huge that I cannot fully understand it yet," said Shcherbakova, herself only 17.

All eyes had been on Valieva, who was in pole position after topping the short program Tuesday and had been expected to add the singles title to the team crown she led Russia to before the doping controversy erupted.

The International Olympic Committee (IOC) had said that for the first time in Olympic history, no medals would be awarded if Valieva finished in the top three because she could yet be punished for taking the banned substance trimetazidine.

In the end, that was not a factor as Valieva, dressed in black and red, fell several times. The teenager had her head in her hands on the ice and then seemed to break down as she waited to hear her score.

It was the latest chapter in a saga that began when a sample from Dec. 25 tested positive for trimetazidine, a drug used to treat angina but which is banned for athletes by the World Anti-Doping Agency (WADA) because it can boost endurance.

The Court of Arbitration for Sport (CAS) ruled during the Games that Valieva could continue to skate in the Olympics, but it did not absolve her of doping and the investigation looks set to rumble on well after the action ends in Beijing.

There will be no medal ceremony during these Games for the team event because of Valieva's involvement.

The doping affair has focused attention once more on Russian athletes' at Olympic Games.

They are taking part in Beijing under the banner of the Russian Olympic Committee because Russia as a country is serving a two-year ban as punishment for a state-sponsored doping program.

'Mind-boggling for Shiffrin'

Valieva's closely watched appearance was the climax of a colorful day at the Olympics featuring a judging controversy, a dramatic crash and more disappointment for U.S. ski ace Mikaela Shiffrin.

A forlorn Shiffrin saw her last chance of winning an individual medal at these Olympics vanish.

The American crashed out of the alpine combined event, meaning she has failed to complete three races and finished out of the medals in two others – an almost unthinkable disappointment for one of the world's best skiers.

Michelle Gisin of Switzerland went on to win the alpine combined, retaining her title from four years ago.

The 26-year-old Shiffrin had seemed perfectly placed after posting the fifth-fastest downhill time.

But in the slalom, a discipline in which she was Olympic gold medallist in 2014, the American went wide on one turn and could not get back on course.

Shiffrin's only chance of any kind of medal is now Saturday's program-ending mixed team parallel.

"I didn’t make it to the finish again and that’s like 60% of my DNF (did not finish) rate from my entire career has happened at this Olympic Games," she said, describing her performance as "mind-boggling."

Camera collision

There was more U.S. disappointment in the women's ice hockey, where Canada beat the Americans 3-2 to avenge a loss in the final four years ago.

Canada raced out to a lead 3-0 in the second period and held on to win to collect the country’s fifth Olympic gold in the event.

"It's just so good, it's a great feeling," said Marie-Philip Poulin, who scored twice.

"It was one hell of an effort. This is redemption."

It was all happening meanwhile in freestyle skiing.

Finland's Jon Sallinen had an unfortunate cameraman to thank after flying out of the halfpipe and colliding into him.

The 21-year-old Sallinen said he thought he had broken his collarbone but he was "lucky not to land on my head".

"I maybe got a little cushion from the camera guy," he said.

In the women's ski cross final, Switzerland's Fanny Smith lost out on a bronze medal when she was penalized for kicking a rival.

Swiss head coach Ralph Pfaeffli said the 29-year-old Smith was too distraught to speak to reporters after the race, but he said he believed the contact was "clearly incidental and not intentional".

With the Games wrapping up on Sunday, Norway top the medals table on 14 golds, Germany has 10 and the United States has eight.