(Adds latest medals, news on injured skier)
* American, Russian men's ice hockey teams meet
* U.S. speed skaters switch to old suits after failures
* Russian skater Viktor Ahn wins third gold for hosts
* Russia's skicross racer seriously hurt in training
By Mike Collett-White
SOCHI, Russia, Feb 15 (Reuters) - Russia and the United States were level at 1-1 in the men's ice hockey going into the final period on Saturday in a Winter Olympics clash redolent of rivalries past, while American speed skaters hoped a change of suits brings a change in fortunes.
There was joy for the hosts when Viktor Ahn led Russia to a one-two in the men's 1,000 metres short track speed skating, but home smiles were tempered by news of a serious injury to Russian skicross racer Maria Komissarova while training.
Doctors made an immediate decision to operate after the crash at the PSX Olympic skicross venue at Rosa Khutor Extreme Park in the Caucasus mountains above Sochi.
"During one of her training runs, Maria injured her spine," team head of press Mikhail Verzhba said. "It is a serious injury.
"The operation is taking place as we speak. Difficult operations take time and it certainly will not finish in the next two to three hours. I do not want to make any conclusions concerning Maria's career, until the operation is completed."
Down in the sun-drenched Olympic village on the Black Sea coast, the big draw was the ice hockey qualifier at the futuristic Bolshoy Ice Dome.
While no medals are at stake, it was being played out before a capacity crowd of around 12,000, most of them roaring on the home team. President Vladimir Putin, whose legacy will partly rest on a successful Winter Games, looked on.
For older fans, minds inevitably turned to the Lake Placid Games of 1980, when a team of American college players defied the odds to beat the Soviet Union's "Big Red Machine" 4-3 and go on to win an unlikely gold.
The "Miracle on Ice" encapsulated the shift in the balance of power between Cold War foes, yet despite fundamental changes since, Putin has evoked the period when addressing Western criticism of preparations for the Games.
That rhetoric has since faded into the background, however, as a generally well organised Olympics, and some thrilling sporting action in Sochi and in the Caucasus mountains that loom in the distance, has won over many doubters.
A relaxed Putin sipped red wine and chatted with the U.S. Olympic team in Sochi on Friday, and heaped praise on U.S. athletes, who are tied in fourth with Norway and the Netherlands in the medals table. Russia is just behind in seventh.
The buildup to Russia's first Winter Olympics was far more frosty.
U.S. President Barack Obama decided not to come to Sochi and, following criticism of Putin's stance on gay rights, sent a delegation including gay officials.
There have also been accusations of widespread corruption and profligacy surrounding the Olympics, which some estimates say cost $51 billion, making them the most expensive ever held.
Putin has dismissed those charges, and some Russian officials put the price tag much lower.
SUITS OR SKATERS?
Of bigger concern for the Americans was how to turn around their wretched form in the speed skating.
After a string of flops, the skaters will ditch their high-tech outfits and go back to skinsuits in the hope that different apparel will drag them back into contention.
The International Olympic Committee announced its approval of the switch back to skinsuits less than hour before the race.
Speculation about the causes of the U.S. athletes' poor start began after double Olympic champion Shani Davis, a favourite for gold after winning three of four World Cup races this season, finished eighth in Wednesday's 1,000m event.
Women's 1,000m World Cup leader Heather Richardson and world record holder Brittany Bowe also floundered over the distance in the women's event on Thursday, leaving the United States still searching for their first medal at the Sochi oval.
Some of that concern was focused on the new "Mach 39" suits made by Under Armour, which Lockheed Martin helped design and was marketed as the fastest-ever in the sport.
All eyes will be on Davis as he goes in the men's 1,500 metres on Saturday, but he faces tough opposition from Koen Verweij, who is aiming to maintain Dutch dominance on the ice in the Adler Arena.
In the rough-and-tumble world of short-track speed skating on the eighth full day of competition in Sochi, China's Zhou Yang successfully defended her 1,500 metres title before Ahn claimed the host nation's third gold of the Games.
Up in the mountains, Anna Fenninger maintained Austria's grip on the women's Alpine skiing super-G title, in a race where just finishing proved a big challenge for the early starters.
Snow conditions have been a major talking point throughout the Games, with clear skies and temperatures of around 14 degrees Celsius in the mountains making the surface soft and slushy, particularly later in the day.
In and around the impressive Olympic village in Sochi, people have been wandering around in T-shirts and swimming in the sea, in a surreal atmosphere for a Winter Games.
Sweden provided the latest upset when they won gold in the women's cross-country 4x5km relay, while hot favourites Norway could only manage fifth.
Charlotte Kalla produced an astonishing comeback leg to earn the shock win. Finland took silver and Germany won the bronze.
Russian Alexander Tretiakov is well set to win a first Russian gold in skeleton, heading into Saturday's final two heats with a useful advantage over Latvian Martins Dukurs.
Austria's ski jumping team, surprisingly shut out of the normal hill final, hopes to restore honour in the large hill event where Poland's Kamil Stoch will be the man to beat. (Additional reporting by Reuters Winter Olympic team in Sochi and Rosa Khutor)