Ghana coach Milovan Rajevac admitted luck was on Ghana's side as they beat Serbia 1-0 in Pretoria on Suday.
Rajevac saw an Asamoah Gyan penalty in the 84th minute give his team three points, after Zdravko Kuzmanovic handled in the box.
"I congratulate Serbia, they played very well, and of course I congratulate my team," Rajevac said. "They played well until the end. Serbia are a very good team, with very good individual players. "They played a wise game today, perhaps we got more lucky than them because we scored one goal and we obtained three points today. I hope Serbia can pick up six points from their next two games."
The 56-year-old, himself a Serbian, paid tribute to his team's concentration, adding he had found the game a tough one to coach.
"This was a very difficult game, difficult to coach. We had to be focused throughout the game, so it was a very difficult game from a technical point of view. We had to maintain our level of concentration to win such a game.''
A win for Ghana against Australia on Saturday could seal a place in the last 16 for the Black Stars, but Rajevac claimed it was too soon to think about their next match.
"I'm still thinking about the game we've just had," he said. "We'll watch the game between Australia and Germany tonight and we will try to concentrate on that, but we have to prepare well because for us this is the most important game.''
Meanwhile, Serbia coach Radomir Antic refuted suggestions that his side were intimidated, and felt that the dismissal of Aleksandar Lukovic for two yellow cards was harsh.
"I wouldn't say we got scared," Antic said. "I would say it's normal to be under great tension at the beginning of the World Cup. Of course the fact that Lukovic got removed from the game was a tough measure. This of course had an influence on the final result.''
Antic also agreed with Rajevac's claim that Ghana had been the luckier of the two side, and that one mistake had been the difference between the teams.
"There was a lot of respect between the teams and one mistake (the penalty) made the difference," he said. "But before that we had several opportunities to score a goal and I think there was a lot of tension throughout the game. I think what made the difference was that our opponents were more lucky than us.''