SOCHI, Russia (AP) -- A rowdy Norwegian curling fan wearing a Viking helmet stood up, held aloft a drink in each hand and went through his catalog of soccer-style chants.
His obvious efforts to lift the Norwegian curling team were to no avail.
Norway had two losses Friday on a day of close results, dramatic finishes and fluctuating fortunes, raising the noise and tension levels inside the Ice Cube Curling Center to previously unseen levels.
By the end of day five, China, Britain and Sweden were in a three-way tie for first place on 5-1 records, tournament favorite Canada (4-2) was tucked in behind the leaders after maintaining its ominous improvement with a third straight win and the United States was knocked almost out of contention after a heart-stopping loss to Russia.
''It was just outrageous out there,'' Britain skip David Murdoch said, summing up the general mood.
As for Norway, losses to the Canadians in the morning and China - the tournament surprise - in the evening left the 2010 Olympic silver medalist 3-3 and probably needing to win all three of its remaining games to advance.
''It leaves us a bit down in the mud,'' Norway curler Christoffer Svae said, ''and we need to crawl our way back up.''
Amid a din that reached a crescendo in the evening as all four games went down to the wire, one voice stood out. Rune Eikeland sang, and he sang, and he kept singing as he stood overlooking the sheet on which Norway played China.
''I was thinking, 'He has to fall asleep soon,''' Norway skip Thomas Ulsrud said. ''He just kept on going.''
Volunteers and security officials came over to calm him down.
''I'm guessing he was a ski fan and that it didn't go well in the slopes today,'' Svae added, ''so he came down to watch a curling game.''
The Chinese proved they are genuine gold-medal contenders by bouncing back from a 6-5 loss to Sweden in the morning session to beat Norway 7-5. Both games went to the last shot.
China started the day as the only unbeaten team, but with some doubts over its big-game temperament and experience.
There shouldn't be doubts anymore.
''Coming into today, I told these guys that they are jumping into the shark tank,'' said Marcel Rocque, a Canadian curling great who has been coaching China for the last eight months. ''Tons of credit to these players of mine for believing that they can compete against these top dogs.''
The Canadians have found the form that helped them sweep through their Olympic trials unbeaten for the first time in the country's storied curling history.
By beating Norway, Canada showed the team has recovered from its sluggish start - and the roar and fierce fist-pump that skip Brad Jacobs greeted his game-defining four-ender in the 7th end spoke a lot of his current mindset.
''That was the most emotional we have been because that was the biggest shot in our biggest game yet,'' Jacobs said. ''I think we were all kind of waiting to explode in this tournament.''
Canada is fourth in the standings but remains the favorite for gold.
The playoff hopes of the U.S. team were dented in a 7-6 loss to the Russians in the most heart-stopping finish this week. U.S. skip John Shuster threw the game's final shot, his stone glancing off a Russian rock and leaving four surrounding the button - two from each team.
Players from both rinks peered over to see which rock was closest - and it proved to be one of Russia's by a tiny fraction.
''He only had to hit it within a millimeter more and we would have made it,'' U.S. player Jeff Isaacson said of Shuster's last shot.
The United States is 2-4 and even finishing with three wins is unlikely to be enough to advance.