GANGNEUNG, South Korea — Dual Sochi 2014 silver medalist Patrick Chan was among the star names to take a tumble but Canada still asserted their position as favorites for Winter Olympic figure skating team gold on Friday. American quad wonder Nathan Chen and Russia's European champion Mikhail Kolyada also fell on the first day of action at the Gangneung Ice Arena. That opened the door for Japan to top the early table after an impressive skate from Shoma Uno, proving more than an able deputy to the absent Yuzuru Hanyu. In the following pairs short program Canadian duo Meagan Duhamel and Eric Radford took second behind European champions Evgenia Tarasova and Vladimir Morozov from Russia to propel Canada from third to first on 17 points. American couple Alexa and Chris Knierim produced a season's best to leave the USA in the silver medal position, three points adrift, with Japan in third. The 27-year-old Chan tumbled on his opening quadtoe loop and again on a triple axel. The Canadian star was in good company, as American men's gold medal hope Chen also slipped up. The 18-year-old had both hands on the floor after missing a quad toeloop, bringing gasps from the crowd. Uno, runner-up to Japanese ice idol Hanyu at last year's World Championships, produced a near-blemish-free short program to put Japan briefly top of the pile, outscoring his rivals by almost 15 points. The team competition continues on Sunday and concludes Monday. Swiss curlers stun US 9-4 In a sport known for its politeness, the sight of American curlers Matt and Becca Hamilton banging their brooms against the Olympic ice in frustration was a bit of a rarity. But then so was the manner in which they lost the game. Despite holding a 4-3 lead heading into the final end, or round, of curling's mixed doubles match Friday, the United States lost 9-4 to reigning world champion Switzerland after the Swiss managed something exceedingly unusual in curling: a perfect score known as a six-ender. How rare is a six-ender? Think of a perfect game in baseball. First, a bit of a primer: Mixed doubles curling, which is making its Olympic debut in Pyeongchang, has different rules to standard curling. There are only two players on each team — a man and a woman — as opposed to four. There are eight ends instead of 10. And each team throws six rocks in each end instead of eight. Although Switzerland was behind by one point going into the final end, Jenny Perret and Martin Rios had an advantage known as the hammer — the right to throw the final stone of the game. They managed to get their first five stones into the house, putting the Americans in a precarious position. Becca Hamilton threw her final rock, which needed to get to the button — the center of the bull's eye-shaped target — in order to preserve their lead. Hard, hurry, hurry! she screamed at her brother, Matt, who was frantically sweeping the ice in a bid to get the stone to the right spot. You got to go, go, go, go, go!! She then raced ahead and joined in the sweeping frenzy as the rock drew close to the button. It was not to be. The stone ended up a few inches past its target, prompting the disappointed siblings to slam their brooms against the ice. Switzerland promptly knocked the Americans' lone rock out of the house and kept all six of their stones within the target's rings, giving them that rare and coveted six-ender. The Hamiltons had another tough game during the afternoon round robin, conceding in the sixth end to South Korea after falling behind 9-1. Norway handed Switzerland its first loss during the afternoon session, beating them 6-5. In other mixed doubles action, Canada and Russian athletes each picked up two wins on Friday against Finland and China. — Agencies