The United States women have been beaten by Switzerland in their opening curling match in a close 7-4 battle at the Winter Olympics in Sochi.

Captained by Erika Brown, the Americans were forced to defend early on against Switzerland's powerful use of the hammer shot and held a slender 2-0 lead after the first three ends.

However, at the fourth end the Swiss started to take control of the contest and won it by three, before adding another two in an equally dominant fourth.

From then on it was a close match, but the US's inability to claim any ends by more than one stone was their downfall as they eventually fell 7-4.