Fanne Rinne scored just 7 minutes into the game Sunday, starting Germany on its way to a 2-1 Olympic women\'s field hockey win over the United States. It was the opening contest of the field hockey tournament, one in which the Americans struggled to get their offense on track. The United States is playing in Group B , where New Zealand downed Australia 1-0 on Sunday and Argentina routed South Africa 7-1. The Americans will play Argentina Tuesday. In Group A action, the defending champion Netherlands blanked Belgium 3-0, China defeated South Korea 4-0 and Britain was a 4-0 winner over Japan.