US inspired by message from Obama
United States coach Bob Bradley spoke on Friday of how moved he and his team had been when President Barack Obama congratulated them on victory over Algeria, DPA reported.
The victory, secured in the final minute, ensured the US finished top of Group C, setting up Saturday's second round meeting with Ghana.
"We're all honoured that before a big match we should receive a call from President Obama," Bradley said.
"We made a visit to the White House a few weeks ago and it was a special moment, but for him to follow up is even better."
Bradley admitted to being impressed by Obama's knowledge of football, or at least how well-briefed he had been. "He even asked how Tim Howard's ribs were," he said.
Howard damaged his ribs in a collision with Emile Heskey during the US's opening draw against England.
The US team also met former president Bill Clinton, who was in Pretoria to see the dramatic win over Algeria.
Bradley is well aware that Ghana, who as the lone remaining African nation at the tournament will have all the local support, will be tough opposition.
"This particular Ghana team is well put-together," he said. "Their coach has done a good job. The team is organised with some very talented individuals.
"They have great athletic ability, and when you look at their style of play, you see talented individuals but fitted well within team framework."
Ghana's "unpredictability", though, he admitted, was a concern.
"They have individual players who are very capable," he said. "You think they're going to pass and at the last second they decide to dribble - you think they'll go left and they surprise you and go right.
"In all teams you must have a balance when you are looking for creativity and mobility. The more you run around, the more dangerous you are but at the same time it can be a problem when the ball's turned over."
The US reached the quarter-finals of the 2002 World Cup, but Bradley insisted matching that achievement was not playing on the minds of his squad.
"We've talked about different goals and we've accomplished the first one," he said.
"Certainly you have moments when you think we're capable, that if we continue to build we can go to the end," he said, "but that has to be balanced with a concentration on each game."