Brazil coach Dunga admitted his side had shown "nervousness and anxiety" in their World Cup opener against North Korea at Ellis Park before running out 2-1 winners.

Maicon made the breakthrough for the five-time world champions with a shot from an acute angle and Elano added a superb second when he sidefooted home a brilliant through-ball from Robinho.

"The first match is always very tiring," said Dunga. "There is a lot of nervousness and anxiety after a lot of training sessions. All of us want to score and not concede any goals."