PRETORIA - Better concentration was the key to a vastly improved performance by Brazil on Thursday as they beat the United States 3-0 for their second win at the Confederations Cup, said midfielder Gilberto Silva. "We were very concerned when we slept a little bit in the first game and lost our concentration," said Greek-based Gilberto referring to a last-gasp 4-3 win over Egypt in their opening Group B game on Monday. "Maybe we were a little bit tired. We did not want to concede two quick goals again and today we were a lot better. "We were very concentrated, particularly in our movement around the park and in our defence. We played naturally and didn't let them into the game." The former Arsenal captain, who now plays for Panathinaikos, said the fluid performance against the Americans was important to re-establish a rhythm to Brazil's play. "Once we scored our first goal everything became natural to us," he added. Coach Dunga, who has taken Brazil on a 13-match unbeaten run, said rest had also been key. "What changed was physiological. Before Egypt we had played two (World Cup) qualifying games and had travelled without sleeping. Now we've had time to rest. We have adapted to the different time zone and prepared well." Next up for Brazil are Italy in their last group game on Sunday. "We are two great teams and you never know what will happen," Dunga added in the post-match news conference. U.S. coach Bob Bradley blamed a tentative start for his team's quick collapse, precipitated by a goal from Felipe Melo after seven minutes. "Brazil are always a difficult team to play but when you go down early it becomes almost impossible," he told reporters after the Americans suffered a second defeat at the tournament. They are now eliminated after losing 3-1 to Italy in their opening Group B game on Monday.