APThe United States are back in action against Australia at the World Cup today, exactly one week after a stellar performance in their opener that sent expectations for the squad soaring.Meanwhile, Brazil get a second chance to look like one of the favourites against Haiti.It remains to be seen how much help the Americans will get from star forward Christian Pulisic in front of what's expected to be an electric crowd in Seattle. Pulisic has a sore left calf and has been working out separately from the team.Brazil will try to improve following a lacklustre 1-1 draw against Morocco last week. The Brazilians are five-time World Cup champions, but haven't won a title since 2002.Also, today Scotland face Morocco and Turkiye take on Paraguay.The Americans are looking for a suitable encore after one of the country's best performances on a World Cup stage. Folarin Balogun scored two goals while Gio Reyna added another in a 4-1 win over Paraguay that exceeded most fans' expectations.Pulisic was often the catalyst while the US scored three goals in the first half, but he came off at half-time after feeling stiffness from a calf injury incurred in training. The Milan winger joined his US teammates for a pre-warmup huddle yesterday while wearing a compression sleeve on his calf, then went inside to do individual work in the gym.Midfielder Weston McKennie said he did not know much about Pulisic’s recovery, but that he hopes he will be able to play.“I know he really wants to be in, and he’s doing everything that he can, and the staff is doing everything that they can as well,” McKennie said.Australia also have momentum after their impressive 2-0 win over Turkey. Nestory Irankunda and Connor Metcalfe scored for the Socceroos, who are playing in their sixth straight World Cup and seventh overall.