Sweden's Stina Viktorsson had another up-and-down day at the World Women's Curling Championship, losing 6-4 to Germany before edging Italy by an 8-7 count.

Viktorsson's foursome, who shocked three-time World and Olympic champion Anette Norberg three times in the Swedish championships, are at 3-4.

Five teams are ahead of them in the win column and there is little room for error over the next two days.

"It's getting better," said Viktorsson, who has a strong World Junior pedigree but is herself a rookie in world women's play.

"It's hard because we usually don't play on this ice, but it's more than that. I can't blame the ice."

Sweden enjoy back-to-back byes before hitting the ice on Wednesday against the Czech Republic.

Elsewhere, China continued their rampage through the field with a 10-1 thrashing of the United States.

Debbie McCormick had two-thirds of her 2003 World Championship team on the ice but crashed early to Bingyu Wang's team from the northern city of Harbin.

"We feel like we got beat more by the ice than by China," said McCormick. "It just didn't happen. I've curled enough to know we can bounce back."

Earlier on day four, China had upset Canada 9-7 to become the only undefeated team.

Wang leaped out to a 3-0 lead after two ends over Canada's Jennifer Jones, and held a 4-1 lead into the fifth, when Canada scored a three.

Tha Canadians then stole one and swapped dueces with China, finally forcing the Chinese to a single in the ninth.

The see-saw battle came to a head in the 10th end. Canada held China to a single in the ninth, and after Wang made a double-takeout on her last stone of the 10th, Jones faced a draw to four-foot rings facing two, but her stone slipped too far, giving China a steal of two and a 9-7 victory.

"I thought we controlled the back half of the game," said Jones.

"We probably should have won it. I just missed my last shot."

Scotland are set to miss the weekend play-offs after dropping to 1-6 following two more defeats, 8-4 to Switzerland and 7-6 to Denmark.

In other games, Russia pasted the Czech Republic 11-4 but were then outscored by Japan 10-5.

China lead the pack at 7-0, with Canada and Switzerland both at 5-1. Denmark and the United States are at 4-2.

Follow comprehensive World Women's Curling Championship coverage live on Eurosport TV and uk.eurosport.yahoo.com! Eurosport is available on Sky 410 and Virgin Media 521; Eurosport 2 is available on Sky 411 and Virgin Media 525.

Eurosport